Sam (Karen Gillan) is an assassin who is abandoned by her employer when she kills the wrong man. So she sets out to show them the error of their ways. 

Left to fend for herself at a young age by her assassin mother (Lena Headey) Sam spends the next fifteen years following in her footsteps to become a formidable assassin. That is until she is screwed over by her male employers, headed up by Paul Giamatti, before being sent on a job where she realises she will orphan a young girl. This results in her taking the eight year old (Chloe Coleman) under her wing and seeking help from a group of librarian gun dealers (Carla Gugino, Michelle Yeoh and Angela Bassett) to get even with her ex employers. 

The film is set in London, but in a sort of 1950’s American kitsch London. Action set pieces will feature slow motion, songs playing, lots of guns and a smattering of knives and hammers.  Films referenced include Kill Bill, Face Off, Leon, Bad Times At The El Royale, John Wick and even The Big Lebowski (check out the Gutterballs bowling alley). Of course that in itself is not an issue at all. Artists are inspired by other artists. It is just that the action rarely clicks at all and some of the fight sequences are downright clunky. 

It is genuinely a shame because Gillan has shown her action credentials as Nebula in the Marvel Cinematic Universe and in the Jumanji reboots. Gugino, Yeoh and Bassett also seem criminally underused. 

Gunpowder Milkshake is a misfire. It takes the pieces of many films the creators clearly enjoyed, pieces them together and does not live up to the same standard.