Dark, seemingly depressing too at first. However, the masterful use of the surreal and the perverse is a delight. This is Olivia Coleman at her very best, playing a wife suppressing so much turmoil that she's plainly the more troubled of the couple - in spite of Julian Barrett's superb portrayal of a suicidal husband. The addition of two deeply troubled but intriguingly bizarre "children" (living at home at 25) makes for even better viewing. Each twist of the story and development of the plot leaves me all the more enraptured - rare indeed in any TV comedy.
This is the sort of TV that only gets made when TV commissioners stop thinking about viewing figures and pandering to the hoi polloi , and instead go for something profound and amusing. The BBC should really be in the vanguard of such things, but they're always too busy in internal politics and demographical soul-searching these days. Thank the Good Lord for Channel 4.