Back in 2009, JJ Abrams had a problem. Off the back of the blockbuster success of Star Trek, he had an idea for his next picture. But not a whole idea...

"It was something about about a train transferring contents from Area 51, but I didn't have any characters," JJ tells TF.

As problems go, it's hardly a catastrophe. Especially when it isn't your only idea...

As a kid Abrams, like his heroes Steven Spielberg, George Lucas and Robert Zemekis, made films on a Super 8 camera.

A cheap, mass-produced home video solution pre-loaded with 50ft spools of 8mm film, Super 8 cameras were a fixture of the American household between 1965 and the early '80s, when VHS rose to prominence. 

JJ called fellow director and friend Steven Spielberg to discuss this other idea.

"We started talking about the kind of films we love to see and the kind of films we'd love to make together someday," says Spielberg.  

"We landed immediately on our mutual history of making 8mm films. We both thought it would be cool to make a movie about young people having an adventure making movies."

So now Abrams had an idea with characters, but no story to drive it.

Bingo! The train.

"I had a premise without characters and these great characters that needed a premise. So I thought if they came together it could be a compelling movie."

JJ picked up the phone...