When Andrew Lincoln was approached by the television channel AMC three years ago for a possible lead role in a television series called The Walking Dead, he was thrilled.
After all, AMC was the acclaimed production home for the Emmy Award-winning dramas Mad Men and Breaking Bad. And the project was to be helmed by the acclaimed film director Frank Darabont; responsible for the likes of The Shawshank Redemption and The Green Mile.
But then the 38-year-old English actor read the first page of the proposal.
"Underneath the title it said: 'zombie, survival, horror'," he says. "I phoned up my agent and said: 'Is this a joke or some elaborate mistake?' And he said: 'No, no, trust me. It's going to be an apocalyptic Lord of the Flies'. And I thought right, I will take your word for it."
His agent certainly earned his commission, as the series went on to inspire a rabid fan following and a Golden Globe nominee last year for Best Television Drama. In the eyes of American viewers at least, the role elevated Lincoln from Keira Knightley's painfully shy love interest in 2003's romantic comedy Love Actually to a vampire-slaying cult hero.
And the actor is just as surprised as everyone else by the immediate success of the series, which is returning from a mid-season break with episode eight of the second season on the free-to-air channel FX on Wednesday.
While the Twilight films have helped make vampires trendy, when pressed further, Lincoln attributes the series' popularity to its cinematic feel.
"It was pitched to me very early on that the production, scale and quality of the programme would be cinematic," he says. "When you read a script, it's rare that it matches the expectation of what you imagined with your mind's eye. From the first episode, this really exceeded it."
The credit largely goes to the creator Darabont, who was intent on building something more than a vampire TV series. Adapted from the ongoing The Walking Dead comic series by Robert Kirkman, Tony Moore and Charlie Aldard, Walking Dead follows the epic adventures of a small group of survivors living in the aftermath of zombie apocalypse in downtown Atlanta.
Led by Rick Grimes (Lincoln), a deputy sheriff before the zombie attack, the group live by their wits as they attempt to escape blood-thirsty zombies who tend to gruesomely savage their victims.
Lincoln sees the vampire theme as a device to discuss more subtle themes of humanity and heroism in the face of danger, something harder to achieve with a straight vampire flick where cheap thrills are often adopted to keep viewers interested.
"In film, you are constrained to a linear two-hour frame," he says. "Where, if you are doing long-term television, you can plant ideas in an audience that comes to fruition a season later. The format for writers on TV is much more character-driven."
However, with TV comes commitment, meaning Lincoln's decision to bind himself to the series for a possible six more seasons also means he may have to turn down higher-profile film roles.
But like his decision to risk his reputation as a promising British character-actor for his twee turn in Love Actually, Lincoln describes his job as a gamble.
"That is essential to me - it keeps my interest and keeps me challenging myself," he says.
"To play the lead role in a zombie, survival, horror series, it's like jumping off a cliff. The audience might say: 'What? The guy who likes Kiera Knightley is this butt-kicking cop?' But that is the joy of what I do. We can keep reinventing ourselves."