Saints and Sinners

Richard Fleet, a top lawyer, is shot dead in his car after a late business dinner with his partner Charlie Muir and a client from the building firm Arcadia. A gun has been left at the scene, which is almost the only thing the police have to work with. Reid and Burke visit the widow, Adele, and come away unsettled: she is less than sympathetic, and she is having an affair with Muir. Neither of them has an alibi for the time of the murder, and neither mentions Fleet's £5m life insurance policy, either.

The case widens when residents Betty McGoldrick and Martha Ramsay turn up protesting a new phase of housing development, convinced that chemical contamination from a long-gone pharmaceutical plant has caused a spate of illness, including the leukaemia in Martha's son Ben. Their legal action was thrown out of court. Burke's surprise grows when he learns that Fleet and Muir represented the residents all along, even while Arcadia paid them. Then Muir is shot on the Arcadia site, another identical gun found near his body, and Turner, the client, dies too, discovered in Fleet's own home with a firearm at his side. Somewhere in the story is a fourth man, unseen at the restaurant on the night of the first murder, and a now-paralysed Muir may be the only one who can name him. The guns are still out there, and so is the fourth man, and the episode is in no hurry to hand either over.

Chris Dolan and Glenn Chandler wrote it, Patrick Harkins directed. Blythe Duff's Jackie Reid, John Michie's Robbie Ross, Alex Norton's Burke and Colin McCredie's Stuart Fraser investigate, with Lesley Harcourt's Gemma Kerr in support. Frank Gallagher is Charlie Muir, Jane Gurnett plays Adele Flett, Campbell Morrison appears as Martin Turner, and Louise Ludgate's Martha Ramsay and Stevie Hannan's Robert Ramsay carry the residents' story.

Three shootings later, the bodies have stacked up faster than the answers, and the script keeps the plates spinning without dropping any. That's no small thing for a story this crowded. The pleasure is very much in the doubling back.