This is a documentary about a women's prison in the UK. It tells the stories of several women. Some of them are there because they had unfortunate childhoods that led to bad choices as adults. Some are there because of just poor decisions without any heavy back story. Many are there (from foreign countries) because they got caught smuggling drugs ("mules".) I went into the theatre not expecting much, except that I'd probably get depressed. This is, however, a very different kind of film. For one thing, the women sing songs about their lives, in various styles, ranging from hip hop to almost operatic. The singing is extraordinarily good, well choreographed, and well filmed.
Also, we get detailed stories from a dozen or so women about what they did to get locked up, and how their lives evolved. This also is fascinating, but of course also disturbing. Many of these women were abused in childhood.
But there are also other horrifying little facts that fall out of the stories. There are two women from France who got 18 years (!) for drug smuggling for professional drug dealers, but there is also a woman who murdered her neighbor in cold blood and got three and a half years! Very scary legal system.
I highly recommend this film as valuable social insight, but it's not for the weak of heart -- very gritty.