A chemist and his assistant make a groundbreaking discovery. They manage to make butter directly from pasture grass without having to deal with either the cow or the use of dairy products. An industrialist attempts to seize the invention.
A cop from the provinces moves to Paris to join the Anti-Crime Brigade of Montfermeil, discovering an underworld where the tensions between the different groups mark the rhythm.
Hoping that self-employment through gig economy can solve their financial woes, a hard-up UK delivery driver and his wife struggling to raise a family end up trapped in the vicious circle of this modern-day form of labour exploitation.