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Martin has two best friends, Patrick and Carl, who couldn't be more different. One is an irresponsible, unreliable, feckless womaniser, and the other is dead.
Guess which one slept with his wife?
Martin Grantham is happily married to Jen. They have a son Dan, a nice house, the works. One day his best friend Carl throws himself under a train, setting off a disastrous sequence of events that will change Martin's life forever...
Into this mess steps Patrick, a friend from way back. Patrick is everything Martin is not – glib, self-confident, popular and pathologically immature. He's the last person Martin needs in his life right now. Or is he?
It's not a matter of life and death; it's much funnier than that.
Marc Warren, Alexander Armstrong and Keeley Hawes are Mutual Friends, a new comedy drama for BBC One
Marc Warren (Hustle, Dracula) is Martin; Alexander Armstrong (Life Begins, Armstrong & Miller) is Patrick; Keeley Hawes (Spooks, After Thomas) is Jen.