Peter Davison as Dangerous Davies

The nickname's ironic, because Dangerous Davies is about as dangerous as a beagle. Shy, shambolic and altogether endearing, he solves the suburban crimes that fall under the radar of more flamboyant colleagues.

"A good policeman who has kind of missed the boat", is how Peter Davison describes his character. And Davison knows a thing or two about being seen as a nice guy. Born Peter Moffett (he changed it to avoid being confused with director Peter Moffatt, who actually ended up working with him on Doctor Who), Davison's been one of telly's saintliest stars since becoming famous as fresh-faced Tristan in All Creatures Great and Small. And, while most people will always love him best as the Fifth Doctor, those in the know will always be in awe of Peter as the man who composed and performed the theme tune for children's classic Button Moon. We kid you not.

Sean Hughes as Mod

Morse had Lewis. Unfortunately for Dangerous Davies, he has Mod – an unemployed layabout whose idea of efficient living is to spend all his time in a library to save on the heating bill.

But, while he's the king of underachievers, Mod also has a pretty sharp and wily mind. Which is why Sean Hughes was the perfect choice for the role. A comedy superstar since becoming the youngest winner of the Perrier Award in 1990 (his record was broken by Dylan Moran a few years later), Sean has long been seen as one of the more enigmatic people on telly. A bit of a career chameleon since leaving Never Mind the Buzzcocks, Sean's embraced serious acting more and more and was even a regular on Coronation Street last year.

Emma Amos as Julie Davies

If Dangerous Davies looks a bit down at times, it could be to do with the up-and-down relationship with estranged wife Julie. She clearly has feelings for him, but is she too exasperated to give the relationship another chance?

Emma Amos has one of those faces that will have you thinking "I know her, wasn't she from...?" And then you might draw a blank. So we'll help you along and say she played Yvonne in the Nicholas Lyndhurst sitcom Goodnight Sweetheart (to be pedantic about it, she was the second person to play the character). Hard-working Emma has been in plenty besides that, from Buddy's Song (yes, the Chesney Hawkes epic) to Bridget Jones's Diary.

Rob Spendlove as Ray Aspinall

Dangerous Davies is used to being the butt of his colleagues' jokes. And one such adversary is his superior, Ray Aspinall. On the plus side, Ray does respect Davies's skills as a detective. Well, sort of.

A veteran character actor who's popped up just about everywhere, Rob Spendlove started out by studying drama and went onto tour schools with a fringe theatre company. It was only a matter of time before he made the jump to telly, and it was a pretty ostentatious breakthrough – starring in the very first episode of Brookside. He's also been in shows from Lovejoy to Dangerfield, but with The Last Detective he's really got a role to sink his teeth into.