Having finally shaken off his popular character “Scrubs” and lost whatever indie movie cred he scored with the solid “Garden State,” Zach Braff seems to be at sea a bit these days.

He’s on the stage these days, starring for the first time in a play he wrote himself that means to talk about life and death, modern life and the kind of important topics the theater is supposed to address. But he does so in a language he knows best – the sitcom.

So his “All New People,” showing in London’s West End after a run on Broadway that featured another actor in his part, is stuck in the rhythms of humor and bombast, pausing occasionally for the serious moment, that seems all the more out of place when it comes.

Braff plays a man at his friends beach house (on Long Island City!) contemplating suicide on his 35th birthday. He’s interrupted by farcical characters, one more outlandish than the next, until at the end they’re four people riding the night out.

Fans of Braff, a pretty good comic talent, may be disappointed that his part seems at first limited to the frustrations of a straightman lashing out at his guests’ excsses or hiding his head in his hands, though he eventually softens up and allows himself some lines.

TV fans may be equally grateful to see Eve Myles, who was so good in “Torchwood,” as a real estate agent who busts up his melancholy. She’s able to do a lot with a look, a face and a reaction that plays to the paying audience, in this case the charmingly cozy Duke of York’s Theatre.

Paul Hilton, as a local fireman who is also the local drug dealer, is a more rote character – Kramer in fireboots. And the dotty blonde prostitute played by Susannah Fielding is right out of central stereotype.

They get off some funny lines here and there, but it’s more surprising what kind of serious intent Braff as playwright is intent on conveying. The title, for example, is from a typically ditzy monologue by the hooker who says she was fascinated by something a  fellow worker at a sex line told her: In 100 years, there will be all new people. We’re meant to laugh at that line, but then Braff goes and names his play that, so maybe not.