Ryan makes a bionic leap from Walford to Hollywood

When Michelle Ryan swapped her role as a cockney resident of Walford in the BBC soap EastEnders to follow in the footsteps of Lindsay Wagner on American television, few could have denied she faced a challenge.

The sceptics have been proved wrong. Ryan, who appears in the latest version of the television series Bionic Woman, has made a successful debut by drawing the biggest audience in its timeslot with 13.9 million viewers. In fact, the show has proved to be the biggest midweek premiere for NBC since The West Wing began in 1999.

Ryan, 23, from Enfield, north London, has done what many British actresses dream of doing. She was a relatively unknown face to American audiences, having played the volatile Zoe Slater in EastEnders from 2000 until 2005. She also had to beat off competition from seasoned Hollywood actresses to land the role.

Her challenge was greater given that the lead role had once been been taken by Wagner, who won an Emmy award for her work in the original series. In 1976, Wagner's character was a former tennis professional who was rebuilt using hi-tech body parts after a skydiving accident in which she lost her arm, legs and part of her hearing. She received bionic transplants for her missing limbs in return for her services as a government agent.

Producers of the new version say the latest Bionic Woman is a wholly new individual. Ryan's character is a struggling barmaid who has been a surrogate mother to her sister's child. After a car accident, her body is rebuilt with secret technology, making her indebted to the facility that "repaired" her.

Ryan began acting as a member of a theatre group when she was 10. She was picked for her role in EastEnders at the age of 15, for which she learned a cockney accent. In 2005 she left and has since mused that her involvement with the show as a much put upon character served as a rehearsal for Bionic Woman. She has had dance training since and attributes this to helping her with the physically demanding stunts needed for the show.

American critics gave Ryan's performance glowing reviews, with the Hollywood Reporter praising her for playing Jamie Sommers "as more conflicted and vulnerable than did her predecessor". It wrote: "As our new heroine, Ryan has the stuff to make it work even better than the first time round."