Ludwig cast: who's who guide

David Mitchell leads the cast of Ludwig , a big new BBC drama, airing on BBC One and already available as a box set on BBC iPlayer.

The six-part series is part drama, part comedy and sees David team up with hugely popular star Anna Maxwell Martin.

It also boasts a great supporting cast and features some big guest stars. Here's a who's who guide to the series...

John 'Ludwig' Taylor ( David Mitchell )

John is a brilliant puzzle setter whose life is upended when his identifical twin, DCI James Taylor, dissapears. John impersonates his police officer brother to find the truth but discovers he actually quite likes cracking crimes.

Lucy Betts-Taylor ( Anna Maxwell Martin )

John's sister-in-law and wife of his missing brother James. She believes James is alive and vanished due to something he'd discovered about a case. She wants John to get hold of her husband's notebook and asks John to impersonate James to get hold of it…

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DI Russell Carter (Dipo Ola)

John's new cop partner. John becomes suspicious of the fact Russell was transferred to the station at the same time James went missing. He's also suspicious of Russell’s close relationship with the Chief Constable.

Chief Constable Ziegler (Ralph Ineson)

A stern figure. John has nagging doubts about Chief Constable Ziegler after finding a photo of him on James's phone. Is he involved somehow in James's disappearance?

DCS Carol Shaw (Dorothy Atkinson)

John’s terrifying new boss he has to call ma'am. She's keeping a close eye on John and is starting to wonder about his odd behaviour like solving murders in a day!

DS Alice Finch (Izuka Hoyle)

Bold and highly ambitious officer, who likes leaping to conclusions which John hastily corrects.

DC Simon Evans (Gerran Howell)

The youngest member of the team who still lives at home, bless! He's impressed by John's quick thinking and is keen to learn.

Holly Pinder (Sophie Willan)

A somewhat mysterious figure in the office who seems to be keeping a close watch on John. Has a talent for computers.

Guest stars

Lady Bryce (Felicity Kendal)

Hotel owner Lady Bryce features in the second episode. She comes to the police's attention when one of her guests strangely goes missing in the middle of the night. Could she be involved?

Megan Rowlands (Ella Bruccoleri)

Megan is a cheery American tour guide who's murdered in a church during episode three. Ludwig must work out why anyone would go on a walking tour of Cambridge and then murder the guide?!