When I was growing up an awkward sitcom scene would be a child walking in on their parents together in bed. The first episode of Such Brave Girls takes things a bit further when Josie (played by the series creator Kat Sadler) walks into the kitchen to see her mother Deb (Louise Brealey) being fingerbanged over the sink by her boyfriend Dev (Paul Bazeley). It sets the tone for a comedy that makes you cringe, squirm and giggle all at the same time.

Such Brave Girls homes in on the messy, mucky lives of sisters Josie and Billie (played by Sadler's real-life sister Lizzie Davidson) and their family and friends. It's a world of scrimping and saving, ducking and diving and trying to have fun despite daily struggles with lack of money and mental health problems.

It's not Mrs Brown's Boys, that's for sure. It is not a studio sitcom with an audience telling viewers when to laugh, it is all on film so there are no laughs to guide you. And some of the scenes in the first episode are as painful as they are comical. Relationship issues, suicide threats, violence. I can't think of many sitcoms that should give out the Samaritans contact details at the end.

But there are also good and proper laugh out loud moments, such as when a hair bleaching session goes horribly wrong due to an Asda bag being put on a head during the process. The chemistry between the two sisters is unsurprisingly strong given that they are real sisters. Other comic touches are more subtle. The visual gag of someone in a car dressed as a witch with their pointy hat squashed down because it doesn't fit.

Pre-broadcast articles about the programme suggest that Sadler and Davidson have drawn on their real lives for Such Brave Girls, which gives great roles to women and portrays the men as hapless or hopeless or both. It made me imagine a female version of Mike Leigh's 1983 film Meantime. In a good way. And with added fingerbanging.

Wednesdays, BBC Three, 10pm or watch it all on iPlayer now.