24 star Mary Lynn Rajskub was pursuing a career in comedy before joining the hit US show.

The actress, who plays computer genius Chloe O'Brian in the drama, has admitted that the role was a big challenge but she is thrilled to be helping Jack Bauer to save the world for a fourth year.

"My background is in comedy and really this is my first dramatic role," Rajskub told The Sun. "I've done a few things in movies but it's predominately been comedic stuff for me, so this has been really great. I like it.

"When I auditioned, on the page the part was just, 'No, Jack. Yes, Jack'. Besides, I had never watched 24. But when I realised what it was, I realised this is a cool show."

Asked whether she is as technically-minded as Chloe, Rajskub replied: "I'm the worst. I can't even turn my television on. If it takes me more than 10 seconds, then I'm like 'I don't have the time for this'. Too many channels, I don't enjoy it. I don't need 600 channels."