I wish I could come up with a way of describing dark comedy without calling it “dark”. It has become a catch-all adjective to describe everything from Frankie Boyle to Julia Davis. And now it is being tossed around willy nilly to describe C4's Flowers.

But then again, as you can see from this shadowy picture of Julian Barratt who plays troubled children’s author Maurice, Flowers is pretty black. And bleak. The action is set in his rambling, shabby country house. Maurice writes his books in the shed, while live-in assistant Shun (played by Flowers boy wonder creator Will Sharpe) does inappropriate priapic illustrations.

All is clearly not as it seems in the household. Eccentric mum Deborah is played by Olivia Colman, doing a turn that is half-dotty, half-disturbed. She is trying to keep it all together – there are a couple of grown-up twins knocking about too – but there is something under the surface bubbling away and surely about to explode.

This is not your conventional sitcom then, but nor is it anything like Camping or The Mighty Boosh. It’s sitcomland but tipped off its axis in a different direction. There are moments which will make you laugh – particularly the house party from hell in the first episode - but this is a series that stretches the genre to snapping point.

The cast certainly makes this all very watchable. Barratt is growing nicely into his middle-aged, furrow-browed face, while Colman can barely put a foot wrong at the moment. It is good to see her back doing comedy – if you can call Flowers comedy. 

Channel 4 presumably sees this as uncategorisable too. They have decided to run it all across consecutive nights in one week starting with two back-to-back episodes, which is pretty unusual these days. Either they can’t wait to be shot of it or they want to give TV viewers nightmares five nights in a row.

Flowers, Monday - Friday, 10pm, C4.