Hardman Jamie Foreman has revealed he was "scared" about joining EastEnders.
The actor, whose autobiography is being serialised in the Daily Mirror, said he leapt at the chance to play Derek Branning because he loved the character, having turned down previous requests to play other roles on the soap.
He said: "I knew I could make Derek a character the 10 million people watching would really love - or love to hate.
"Then it hit me: I'm going be in EastEnders. It was scary. After years making movies, I was in at the deep end and it felt wonderful.
"I was starting all over again."
Jamie said he wished his character had got the chance to "lock horns with Peggy", played by his friend Barbara Windsor before she quit the soap.
But he said: "We've got plans to take Derek off in an interesting new direction, which will be a real challenge for me as an actor."
Jamie, whose autobiography reveals his real-life gangster past, said walking into the Vic when he first arrived in Albert Square felt like "sliding into a comfortable pair of slippers".
He added: "For the moment, EastEnders is where I'm at and I'm loving every moment of it."