Fifty years ago, England was invaded. At least, that's what the headlines claimed.
The invaders? Fans of two-wheeled transport. They were the mods and the rockers who, if the media was right, were "roaring", "rampaging" and hell-bent on "beating up" the seaside in an "orgy of hooliganism". But was that really what happened?
Leather or sartorial elegance?
Strange as it might sound, if you were a teenager in 1964 this could well be the most serious question in your life.
Cow hide and motorbikes and you were a rocker. Opt for a designer suit and a scooter, and you were a mod (a compaction of 'modernist').
Half a century ago, these two groups descended on the Essex seaside town of Clacton over the same Easter weekend.
Whether or not the clashes amounted to the rioting portrayed by the media, there were fights.
Some of them involved Alan Jones, a rocker brought up in Dagenham.
Mr Jones, who now lives in Clacton, still has the bike he rode into the seaside town in 1964.
He said that Easter in Clacton was an explosion of troubles whose fuses had a long trail.
"I don't know where the mods came from really," he said. "They used to come down to our cafe and wanted to take it over.
"So we used to beat them up and chuck their scooters in the river and all that lark."
He added: "They wanted to be better than us and we weren't going to stand for it.
"It had been going on behind the scenes and we knew there was this weekend coming up so we thought we would go and sort it out once and for all.
"We knew we were going down there for a rumble. We planned it and I think the mods planned it as well."
And yes, he fought.
"I took on about three or four mods and I got a deck-chair over my head. It was just one of those things.
"We had to make our stand against the mods. And I think we won."
Vehemently still a rocker, Mr Jones's attitude towards the old foe has softened, not least as a result of practicalities.
"I don't think I'd be fighting now if I met a mod. I'm 71," he said.
If there were acts of violence that weekend, there were acts of kindness too.
Shirley Hall, a mod, rode into Clacton with a protective escort of rockers after they stopped to mend her scooter.
"The rockers helped me no end," the 68-year-old said.
"Because I had to work until midday on the Saturday, my friends all went earlier. So I went to Clacton on my own and I had a nut come off my flywheel so I stopped.
"A group of about eight or nine rockers came and they were jeering and then one of them said, 'It's a bird'.
"I said hello and told them I was having a problem."
The rockers stopped, fixed her scooter and then offered to escort her to Clacton.
"So there I was in the middle of them, a mod being escorted to Clacton by rockers.
"About a mile outside Clacton they told me to go in on my own because I wouldn't want to be seen with rockers."
But Mrs Hall, whose beloved £65 Vespa Sportique was later given to the fire service by her father to use for fire practice, has a very different memory of the clashes to Mr Jones.
"I didn't see any fights or any trouble," she said. "We were just lying on the beach when the police came along.
"There were people being chased. When I got back my parents were very worried. I told them we had just had a good day out."
Some might wonder what became of these hundreds of young people who were labelled "hooligans" at the time.
Well, Mrs Hall went on to enjoy a successful career as a police officer.