Daniel Mays joins the cast of Line of Duty series three

The Mrs Biggs actor will play Sergeant Danny Waldron, leader of an Armed Response Unit, who will be investigated by AC-12's Steve Arnott and Kate Fleming


Daniel Mays has joined the cast of Line of Duty series three. 


The Mrs Biggs star will play Sergeant Danny Waldron alongside AC-12 detectives DS Steve Arnott and DC Kate Fleming (Martin Compston and Vicky McClure).

Waldron is described as the “highly proficient leader of an Armed Response Unit whose unpredictable behaviour is becoming a threat to colleagues and suspects.” 

AC-12 – headed up by Adrian Dunbar’s Superintendent Ted Hastings – are called in to investigate Danny’s conduct, even though it could mean they find themselves in the firing line. 

“I’m absolutely thrilled to be joining the unbelievably talented cast of Line of Duty series three,” said Mays. “Jed Mercurio has once again delivered a thrilling and emotionally raw script which I feel incredibly honoured to be a part of.” 

Line of Duty’s creator, Jed Mercurio, added: “I’m deeply grateful to the BBC for giving me the opportunity to work on another series of Line of Duty. I’m very much looking forward to resuming a creative partnership with our regular cast, crew and production team and to working with the hugely talented Daniel Mays on this riveting character.” 


Line of Duty returns to filming in Belfast later this month following a critically acclaimed second series starring Keeley Hawes as double-crossing DI Lindsay Denton. The role won Hawes widespread praise and the BBC commissioned two more series off the back of the show’s success, although there is no word yet on whether Denton will make a reappearance.