Deus ex Machina (1)

Two problems land on Boyd's desk at once, and neither is a normal Monday. MI6 asks him to reopen the case of an Iraqi dissident who was killed some years ago. And in Sudan, a man running for President announces a hunger strike, sewing his own mouth shut, to protest Britain's refusal to return the skull of the Mahdi, the 19th-century leader whose remains vanished after Omdurman. The Foreign Office, suddenly very interested in finding that skull, leans on the Cold Case Squad until they move.

It's an audacious premise for a police procedural: a missing skull from 1898 driving modern diplomacy while a murder inquiry runs underneath it. The episode earns the audacity mostly. The colonial history isn't set dressing here; the hunger striker has turned an old imperial embarrassment into live ammunition, and everyone in Whitehall knows it. Boyd, meanwhile, gets to be his usual self, prodding at an official story that MI6 would clearly prefer stayed shut.

Trevor Eve leads as DSI Peter Boyd, with Sue Johnston's Dr Grace Foley, Wil Johnson's DI Spencer Jordan and Félicité Du Jeu's DC Stella Goodman around him. Tara Fitzgerald is Dr Eve Lockhart. The guest list is strong: Alex Jennings as James Andrews, Polly Walker as Catherine Braithwaite, Lisa Jackson as Elaine Wilson, Graham Crowden as Cyril Barrett and Houda Echouafni as Leila Jaffiri. Crowden in particular gives the old business of empire a human face.

Nicholas Blincoe and Barbara Machin wrote it, Andy Hay directed.

Part one spends its time laying out the board rather than moving the pieces, which occasionally drags, but the two cases pull against each other nicely: one wants discretion, the other demands a spectacle Britain can't control. Watching Boyd stand between them, being told by everyone what he can't investigate, is half the pleasure. The skull may or may not exist in any findable state. The embarrassment definitely does.