Katherine Kelly has joined the cast of 'Liar'.

Katherine Kelly

Katherine Kelly

The 'Cheat' actress will star as DI Karen Renton in the second series of the ITV drama, which will see her alter-ego attempt to uncover clues about Andrew Earlham's (Ioan Gruffudd) grizzly past in the three weeks leading up to his murder.

Executive producers Harry and Jack Williams said: "It has been a joy returning to Liar and our reunion with Joanne and Ioan.

"Equally we are thrilled to have Katherine Kelly on board as DI Renton after her stellar performance in 'Cheat'."

Howard Charles and Amy Nuttall have also joined the cast of the second series as Carl and Winnie Peterson respectively, and Joanne Froggatt will reprise her role as teacher Laura Nielson.

Laura will no doubt be one of the main suspects for Andrew's murder after she uncovered his dodgy secret, which led to an arrest warrant being issued for the sexual assault of 19 women.

ITV's head of drama Polly Hill added: "We're delighted both Joanne and Ioan are returning to 'Liar' as Laura and Andrew with Katherine Kelly joining the cast as DI Karen Renton.

"We're sure audiences will once again be gripped by the story as Harry and Jack Williams keep you guessing over who killed Andrew."

Filming for the second series has got underway, and comes after the first season was ITV's highest rated new drama of 2017, with 9.1 million tuning into the final episode.

Jan Diedrichsen, executive director, SundanceTV and Sundance Now, said: "We are thrilled to be working once again with our partners at ITV, Harry and Jack Williams and this exceptionally talented cast on a thrilling new season that will dive deeper into the complicated relationship between Laura and Andrew and the mystery surrounding his death."