Tensions simmer when Jay plays host to Gloria's mum and sister. Phil, meanwhile, tries to solve his kids' problems.
Someone threatens Lindsay's life; the women investigate the decapitation of a wine broker.
Following the storm, a mudslide causes many injuries; Meredith faces a decision that will impact a loved one; Callie is rocked by Arizona's infidelity.
The squad continue to grapple with the clues provided by a serial killer in the hope of saving a potential victim. Reid discovers that details from his personal life might be able to help them solve the case.
Desperate to locate a missing woman, Frank arranges a meeting with Mexican drug dealers; Ray, Ani and Paul close in on the killer but have a hard time keeping their own problems under control.