A new chief shakes things up at Firehouse 51. Violet and Novak work to uncover the truth behind a car crash. Cruz keeps a watchful eye on Severide and Damon's growing bond.

Maggie is a tough and ruthless member of the all-female Dark Moon biker gang led by the merciless Trigga. After Maggie's cousin is drugged at a party, the gang rides out for revenge.