Plumbers, hairdressers, street-sweepers - anyone can be a target of capture, torture and even murder.
Millionaire ransoms are demanded - but with kidnappers accepting sums as low as US$500, it means no-one is safe.
Victims' names have been changed.
“Kidnapping someone in Mexico is like being a rock star. You get anything you want,” he says.
He looks friendly - young, smiling, polite, a bit of a joker. But there's something about his look.
“I normally stare at the victims, let them see my eyes,” he says.
“'Just co-operate,' I tell them. 'Be nice, because if you don't, I will fuck you up. Little by little, by hitting you, burning you or chopping you into bits.'”
Maria loved playing with her dog. She would wave goodbye to her husband Jose and their daughters, aged six and three, as they set out for school and work. Then she would take the animal into the garden.
But that morning, soon after they left, Maria heard a loud bang and the cries of children in the distance. She and the dog both stopped playing and stood still to listen.
Next door's gardener was washing a car. He also stopped, looked up, and caught Maria's gaze. “That was a gunshot,” he said.
Maria ran inside, already sensing that something had gone wrong.
Like many middle-class Mexican families, they lived in a gated community which had its own security guards at the front entrance. She called them, and then rang her daughters' school. “Please call me back once they arrive,” she told them.
In a flash she got changed then ran to the security post. Yes, they had seen her husband's vehicle leave, but no, they hadn't seen anything else.
Her panic mounting, she got into her car and started driving towards her children's school, phoning parents of their classmates on the way.
Getting there, she was told the girls had never arrived. She turned round, and rushed back home, stopping only at the gate where the guards had started going through camera footage.
One of the guards had found a pair of Maria's daughter's shoes lying on the road.
Police started arriving, and began to retrace on foot the route from the house which the family would have taken.
They didn't have to walk for long before they came across a pool of blood on the road. At that moment, Maria's phone rang.
It was what kidnapping experts term “the first call”. She could hardly understand what the person on the line was saying, apart from the words “daughters” and “girls”.
It was however the confirmation she had been dreading: Jose and the girls had been kidnapped.
A kidnap negotiation is often described as a game of chess between a kidnapper and a negotiator.
Every move leads to another from the kidnapper. The life of a person, sometimes even a young child, is what's at stake.
The negotiation has become such a skill - a game - that it's not only the police who are getting trained to do it.
Many criminals too have sought to make sure they have their own skilled negotiators.
Police say there are even “negotiators-for-hire” who offer their services to kidnappers.
The victims' negotiators, whether privately hired or working for the police, never speak directly to the kidnappers. Instead they nominate someone close to the victim to become the voice of the negotiation.
“We assess the candidate's temperament and abilities,” says Rafael, a police negotiator who cannot be identified by his real name. “We try to gauge how they react under pressure. Some people are very explosive, some are calm.”
Sometimes people seem fine, but then fall apart when they first hear the kidnapper's voice… The truth is, it's an incredibly difficult job to handle the calls.”
“They get more and more aggressive, especially if the kidnappers' demands are not met immediately. That's where we try to help and provide support,” he says.
“Choosing the correct person to talk to the kidnappers is the key for success,” says Max Morales, a private kidnap negotiator for more than 20 years.
In choosing a candidate, negotiators will look for anything which could potentially provide an advantage with the kidnappers - gender, age, tone of voice, even their accent.
Police told Maria it was not a good idea for her to be the voice of this negotiation. She ignored their advice.
There was no chance I wouldn't do it. This was about my daughters' safety.”
The negotiators will move into the victim's family house for the duration of the case, which can be a matter of days or weeks.
By staying inside they are available to give advice at all times. But it also means they can avoid being spotted by the kidnappers, who may be monitoring the property.
They will also be on hand to help the family deal with phone calls, to try to keep them thinking positively, and also, crucially, to help negotiate the ransom.
“This is a crime about greed, and it usually finishes with some money being paid,” says Morales.
Our job is to try to make sure the money paid is not what the criminals ask for, because if you pay too quickly, you could be asked for more or even get kidnapped again.”
And if the person chosen to do the negotiations falters, the case starts to dangle on a thread. Changing negotiator midstream is risky too, says Morales, as it can make the kidnappers more anxious and that can be disastrous for the victims.
Some of these kidnappers are pure evil. They sometimes hit the victims, rape them, burn them with cigarettes or a blowtorch or even mutilate them and send the body parts to the family.”
A police negotiator, who can't be identified, remembers the case of a kidnapper who used to send shocking videos of the victims to their families by WhatsApp.
If the victims were men he would show them being beaten up. If they were women or girls, he would apparently film himself touching them sexually.
However, when this kidnapper was finally captured, it was discovered that he had been staging the beatings by putting Bubble Wrap beneath the victim's clothes so they wouldn't be hurt too much.
He would also use some cunning camerawork to pretend that he had been fondling his female victims.
However Machiavellian this behaviour, it's considered an exception to the rule. Physical violence to victims is common, and often gangs get to be known by their sadistic practices.
One notorious gang was called “Nequis”, Spanish for “little fingers”, which they would cut off and send to victims' families.
And Mexico's most famous kidnapper, now in jail, was Daniel Arizmendi, also known as “The Ear Chopper”. What he did to his victims is self-explanatory.
“The riskiest moment is when you've paid the ransom and you lose communication with the criminals, as they have yet to fulfil the promise of freeing the victim,” says Morales.
Police say that the majority of cases end up in a rescue, or in a release, after a ransom is paid. But there are other cases when families pay and never hear from their loved ones again.
“We are sometimes able to match the criminals' voices to those in our database and that allows us to know who we're dealing with,” says the police negotiator.
“This sometimes allows us to know if it's a gang that wants a quick solution or if it's a group which rarely returns the victims even after payment has been made,” he says.
Private negotiators have tariffs, and some work for insurance companies (kidnap insurance is popular in Mexico).
On the other hand, the police negotiators work for free, and frown upon the use of private negotiators.
Those who can afford it reach out to private negotiators and tend to keep the cases hidden from the authorities. These cases rarely reach the official statistics.
Government figures in Mexico indicate 1,500 to 1,700 cases in the past year. But these were all incidents where an official report was made.
According to the National Institute of Statistics of Mexico, the real number of kidnappings could be well over 100,000 each year, based on household polls carried out in 2014.
The institute says its data shows that barely 1% of kidnappings are taken to the police, which is why they believe the situation is much worse than the government admits.
Police corruption is one of the main reasons people don't immediately file a report.
“Unfortunately there is a shocking amount of police involvement in kidnappings,” says Morales.
This can be former policemen who have the know-how to avoid arrest, or even serving officers. The lack of trust in the authorities is a historical and structural problem for Mexicans, especially when people see what happened in places like the state of Morelos, during the 1990s.
There, the chief of police, the head of the anti-kidnapping unit, the prosecutor and several other police commanders were jailed for crimes including aiding kidnappers and torturing victims.
“We've tried to clean up our institutions since then,” says Adriana Fernandez Pineda, the current prosecutor in charge of Morelos's anti-kidnapping unit.
Our challenge is to win over the trust of the people. If we show that we are doing a good job then our citizens will spread our results from mouth to mouth, and that is more effective than any advertising campaign.”
Morelos still figures high in the rankings of kidnappings in Mexico, but Fernandez Pineda says the numbers have been recently coming down due to a major restructuring of the force and to a programme run with the US government.
“Police corruption is part of the problem we have to deal with,” says Rodrigo Archundia Barrientos, head of the anti-kidnapping department of Mexico State.
“It doesn't only happen here, it's something that's present in every country, in some more than others,” he says, adding that new technology including voice detection and surveillance tools have helped cut the number of incidents.
But Morales is still not convinced. “I don't feel that this crime has gone down. What has gone down is the trust in the authorities.”
The authorities try to minimise the kidnapping figures to make society believe that they're working hard on this, but the reality is that the amount of kidnappings has surpassed all limits.”
Meanwhile for Maria, the negotiation had reached a crucial stage.
There are two things it's hard to forget since encountering Crack, the kidnapper who describes his job as being like a rock star: his smile and the way his eyes looked at me.
As he describes how he threatens his victims - “hitting you, burning you, or chopping you into bits” - his look changes dramatically and his pupils shrink.
Crack says he rose through the ranks in the criminal world. First selling drugs, and then moving on to “the dirty work”, or has he puts it, being one of those “who kill and do all the messy things”.
It's incredibly rare to hear first-hand from a kidnapper. Crack spares no details.
To get to the victim you can go through his girlfriend, for instance. You grab her, boil a pot of water and tell her 'tell me where he is or I'll pour this on your face'. They normally give them up.”
“It works with wives too, if you threaten their children with a pan of water, they'll hand over their husbands. It's not difficult,” he says.
Max Morales, the private negotiator, says that “in the majority of cases it is someone close to the victims who gives them up to the kidnappers”.
Crack mentions using attractive women to lure men into a kidnapping, or finding out from workers inside a business what the owner's routines are.
He also says that nightclubs are a place to pick up easy targets.
It's very unusual to have the opportunity to challenge a kidnapper on why he makes victims and relatives go through so much suffering.
Does he ever think about this? Has he ever felt any remorse?
Kidnapping is drastic, and quite cruel, but I don't feel any remorse at all. Sorry, I just don't.”
Crack is an example of how the booming business of the drug cartels in Mexico has spilled over into other crimes, such as kidnappings or extortions, sometimes to replenish their cash reserves.
I met two elite officers of the Mexican Federal Police, who had been recently assigned to deal with kidnappings.
They had recently been working in the border state of Tamaulipas, which has one of the highest levels of drug-related violence in Mexico.
There, they helped dismantle a gang of kidnappers, who were part of one of the region's powerful drug cartels.
It was an incredibly well organised cell, with subgroups to carry out surveillance duties, logistics and an armed group to do the actual kidnapping.
Some members were former military, and one had even been part of a Central American country's special forces.
But police sources say there are many kidnapping gangs which are nothing to do with organised crime.
“In the north of the state of Mexico it's more about gangs who started as small-time robbers, who did some carjacking and then moved on to kidnappings,” says one police negotiator.
“But to the south, the proximity to the states of Guerrero and Michoacan, both hot spots for drug-related violence, means that you'll see more gangs linked with a cartel.”
For Crack, the decision to set up as an “independent” kidnapper has advantages and disadvantages.
“Yes, you have your own guys and you decide what you do, but if you get caught in a mess then no-one will give you economic support,” he says.
Crack finishes our meeting saying he has already ruined his life and acknowledging that he's clearly “sick”.
But some of his last words still reverberate.
Every day there are more and more of us. At some point, you're going to end up with a neighbour like me.”
It's a chilling prospect for Mexico's rich and poor alike.
One man whose wife and children were kidnapped in 2015 says the kidnapping “changed my life… my wife hardly leaves the house any more and I'm always afraid”.
Most of the cases I heard about involved ordinary people who are not wealthy. One street-seller was held for a ransom of US$500.
Another victim was a man who owned a small metal workshop in a rural province of Central Mexico; other cases involved a hairdresser and a bus driver.
“Twenty years ago this was a crime that only affected rich people, but now it's more and more widespread - even the very poor are victims,” says Morales.
“When a poor person is kidnapped it's normally because they've received some extra money and there's a greedy person in their area who wants to take it away from them.”
Almost 24 hours after Jose and the children went missing, Maria's phone rang again.
It was the middle of the night but she quickly picked up the call. This time she could see the number of the incoming call.
Someone calling himself a corporal said: “I have your girls. They're OK.” She heard the words clearly but then the call was cut off.
Against the advice she had been given by the police, she rang straight back.
It was the same man. And it was a soldier who was part of the security forces deployment that had been looking for her family. And, yes, the girls had been recovered.
She raced to meet them at a place the corporal identified. “The closer I got to the place, the more police cars I would see. At one point we couldn't get through so we had to leave the car and started walking.”
The girls were fine. Maria managed to reach them inside a police van.
I felt my soul returning to my body when I saw them. I started to cry and they cried too. One of them was still clutching a bag of toys that her dad had given her.”
The girls later explained that once they had been taken to the safe house by the kidnappers, they had been separated from their father, who they didn't see again.
Men carrying guns kept coming in and out of the house they were being held in.
They could see the windows and noticed the men jumping over the fence and going into the next-door house, often returning with weapons.
Late in the evening, more than 12 hours after they had been kidnapped, one of the men spoke to the girls, telling them not to move.
“Your daddy will pick you up soon,” he said.
Once he had left, the six-year-old started wondering to herself: “How will my daddy get in here?”
It didn't seem right to her, so she quietly got up, went over to the door and pushed it. To her surprise, it opened.
She grabbed her little sister and made for the door. The three-year-old pulled back, saying that they ought to wait for their daddy. But the older girl insisted and the girls ran out, barefoot.
They reached some houses and started knocking on the doors, trying to wake people up. As it was by now the middle of the night, no-one came out.
Then they knocked on a house where there were dogs. The animals bounded out of the house, terrifying the girls.
But the noise also woke another household and when they came to investigate they found the girls. They called the police immediately.
“I was so happy to see them again,” says Maria. “Shortly after they took us home and told me that they would continue looking for my husband.”
Jose had not been so lucky. He was suffering from a gunshot wound - the initial bang which had startled Maria and her dog - and was being held in a filthy bathroom.
He was kept for day and night, day and night. The only care given to his wound was a splash of alcohol and a plaster.
Four days after being captured, and with his wound getting worse, the kidnappers brought in a doctor to see him. He told them that Jose would “live for two more days”.
The kidnappers debated what to do, but the next evening, told Jose they were going to let him go.
They bundled him into a car and dumped him on a patch of waste ground. There were houses nearby, but he was so weak he couldn't move.
He says: “I remember seeing house lights, so I repeatedly cried for help.”
Eventually an elderly man and his grandson happened to walk past and heard him yelling. They called for help.
“That night I got another call on my phone,” Maria remembers.
“'Your husband has been found', I'm told.” She raced to the hospital, but because of heavy rain got stuck in traffic.
When she eventually arrived, before she even saw Jose, she was told by staff that she needed to tell him straight away that the girls were OK.
“He was in a bad shape, but he was back,” she says.
The girls' bravery had probably helped bring the situation to a conclusion, police told the couple.
Without the girls, the kidnappers' leverage had been significantly reduced - and thinking that Jose might not survive, the kidnappers must have felt their position weakening.
Jose chuckles sardonically when asked if he feels lucky for how it all ended.
He's spent months trying to recover physically since the kidnapping, and has been close to dying on two occasions. He's still unable to walk because of the gunshot wound.
“If we're looking for good things that we can pick up from this ordeal, maybe I can say it made us all stronger,” says Maria.
“During the kidnapping the negotiators told me: 'Madam, we've not see you cry yet.' I told them: 'I don't have time to cry, I need to do what I have to do to get them back.'”
'I'm going to get them back because I'm going to get them back', that's all I was thinking.”
Jose says he doesn't talk too much with his family about what happened - that he has tried to move on. Both he and his daughters have needed therapy to help them in their emotional recovery.
But his face lights up when he thinks that his kidnappers are currently in jail and have been given lengthy sentences - for which there is no appeal. They will probably spend the rest of their lives behind bars.
He's been traumatised. So have his daughters and his wife. He may not walk again.
But Jose believes that in the end, he won.