Bristol. A city of such a size that it's possible to maintain a low-profile but not quite substantial enough for a person to entirely stay hidden. As bigamist Andrew Marsden (Stephen Mangan) discovers, you can only keep two families apart for so long (15 years in his case) before connections are made, masks start to slip, and the truth is tantalisingly close to being unveiled.

In the Bliss scenario, he is only able to keep his double life schtum by being the 'anonymous travel writer', making a living by cribbing from TripAdvisor reviews and spending a stretch of time with one family while pretending to the other that he's in locations including Dubrovnik and Inverness. He has two cars, a locked office in both homes, two wives (Heather Graham and Jo Hartley) and a pair of teenage kids (Hannah Millward and Spike White) who he has to keep apart all costs.

During the course of six episodes, Marsden works like a demon to cover his tracks, with some on-the-spot decision-making resulting in him variously self-harming, taking indecent photographs, pretending to be Islamophobic, and repeatedly bashing his head on a desk to make it look as though he's been in a fight. This could only have a chance of working successfully with a convincing lead, and Mangan has been blessed with a wonderfully expressive face which can switch his mood between states of clunky affability, eye-watering anxiety and full-on anger in a second.

There are a couple of plot twists to keep viewers on the edge of their toes, but the main voice in your head is simply trying to predict how Marsden's secret will be exposed. This is the challenge of creator David Cross (Arrested Development, Mr Show) who perhaps threw us a Hitchcockian MacGuffin in pre-publicity interviews by noticing that in many real-life cases serious illness is often the bigamist's undoing. Here, the net begins to close in a far more convoluted, unguessable and entertaining manner.

Episodes watched: all 6

Bliss starts on Sky One, Wed 14 Feb, 10pm (also available live and on catch up via NOW TV)