In the 1980s and '90s, Frank Sidebottom was a giant-headed, cartoon-eyed, cult comedy hero - but few knew who was behind the mask. A documentary is now telling his full story for the first time.
When his head was on, the man behind Frank Sidebottom would never answer to his "real" name.
"If he was wearing the head, you couldn't talk to him as Chris," says older brother Martin. "Even me."
"It was like method acting really," reflects BBC Radio 2 and 6 Music DJ Mark Radcliffe, who was in Sidebottom's band.
With his absurd, anarchic humour and childlike innocence, Sidebottom was a hit with Saturday morning TV audiences and late-night pub crowds alike.
He and the world he created were so convincing, it barely crossed the minds of most of those watching there had to be a real human being inside.
But the man underneath the hot, uncomfortable fibreglass head was Chris Sievey, a musician, artist and comedian from Manchester.
When Sievey died in 2010, memories of Sidebottom could have swiftly faded, only to be dredged up occasionally on nostalgic clip shows. But there is an enduring fascination with both Sidebottom and his creator.
In 2014, Michael Fassbender played a character closely based on Sidebottom in the film Frank. Now the documentary Being Frank examines Sievey's brilliant, underappreciated and ultimately sad story.
Before pulling on the giant head, Sievey tried to make it as a musician in his own right. He and his brother once recorded a session for Apple Records and he formed a band called The Freshies.
Their biggest hit, I'm in Love with the Girl on the Manchester Virgin Megastore Checkout Desk, reached number 54. The documentary suggests it could have been massive, had a BBC technicians' strike not scuppered their hopes of an appearance on Top of the Pops.
It also shows Sievey as a restless, innovative artist who pushed at the boundaries of music and technology. He proclaimed video to be the future long before the days of MTV, while in 1983 he issued a 7" single with a song on one side and an accompanying ZX81 computer game on the other.
A clip of Sievey showing daytime TV host Nick Owen how to play it is in the documentary, proving he was taken seriously by some at the time.
But the big break kept eluding him - until he decided to wear a papier mache head to a fancy dress party and Frank Sidebottom was born. Initially, the character was meant to be the Freshies' support act and number one fan.
"But gradually people liked the support act more than they liked the band," Being Frank director Steve Sullivan says.
"Over a process of years he became Frank Sidebottom, and as far as the public were concerned this guy called Chris Sievey didn't exist any more."
Sidebottom's fame peaked in the early 1990s when he was a regular on Channel 4 game show Remote Control and had Frank Sidebottom's Fantastic Shed Show on ITV. His other appearances ranged from children's TV to the Reading Festival.
In 1989 he warmed up for Bros at Wembley Stadium, performing his rendition of Bohemian Rhapsody for 55,000 people - although he was eventually booed off by the predominantly teenage crowd.
Sullivan says: "Chris couldn't have done that for so long if he didn't love it, and he obviously enjoyed coming up with all the hilarious different versions of Frank, different outfits for Frank, different situations for Frank.
"But I think over the years, Chris knew that what he wanted to do was be recognised as Chris Sievey the artist."
Mark Radcliffe agrees. "There were times when Chris resented Frank, because Chris wanted to be a pop star," he says.
"He was a good pop writer and a good musician, and he could make records really well. I think Chris wanted that more than anything else."
Sievey often worked day and night on his all-consuming creations, whether it was making music or creating intricately designed comics, costumes or sets for Sidebottom.
"He was obsessive about everything he did," says Martin Sievey. "It had to be his way. And because it was his way, he would put 110% into it."
Radcliffe adds: "He was full of ideas but he would carry them all out."
The DJ recalls one occasion when he remarked on the boredom of life in a tour van and said they needed some games to play.
The next time Sievey picked him up, he had installed a half-size snooker table across the back seats.
"There was hardly anywhere to sit, and then every time we went around a corner all the balls went over the other side of the table. So he said, 'I've got the solution to this - Velcro balls!'
"That was Chris. And that was nothing to do with the gig. His approach to life was the same as his approach to being on stage. If there was a laugh to be had out of it, then why not do it?"
Sievey struggled with alcohol problems before his death at the age of 54. He was virtually penniless when he died and was only spared a pauper's funeral when another former member of his band, author Jon Ronson, rallied a crowdfunding campaign.
Radcliffe believes the lingering affection for Sidebottom comes down to his innocence and enthusiasm for life, and because he acted as though he didn't care what anyone thought of him. Those were traits he shared with his creator.
The broadcaster says of Sidebottom: "Even though he's a fool and he's a buffoon, in a way he's an everyman. His approach to life was better than most other people's approach to life.
"It was a completely uncynical way of living. It was a way of being driven by your enthusiasm. And Chris was a bit like that."
Being Frank: The Chris Sievey Story had its premiere at HOME in Manchester and is out in the UK on 29 March.