Grimm Season 5 Episode 1 picks up where the Grimm Season 4 finale left off: Juliette is dead, Nick's mom's head is in a box, and Agent Chavez arrives to kidnap Trubel. In the struggle, Nick is incapacitated. When he wakes up, there is no sign that anything bad happened: no body, no box, no head, no Trubel.
Confused and upset, Nick puts the pieces together and realizes that Chavez is behind the kidnapping of Trubel and likely the clean-up of his house. Over his friends' concerned objections, Nick decides to confront her. When he pays a visit to her office, she denies everything and throws him out and then reports his erratic behavior to Renard, who warns Nick to stay away from Chavez.
Nick goes to Chavez's house and kidnaps her, taking her to the spice shop to interrogate her. The truth about what happened comes out, and Chavez agrees to take Nick to get his answers. When they arrive at their location, however, they find that her contacts are all dead and then they, too, are ambushed.
In the ensuing fight, Chavez is fatally wounded. Giving Nick Trubel's rook chess piece, she warns him about "them" coming, but dies before she can tell him anything else.
Adalind goes into labor and gives birth to a baby boy, which she names Kelly in honor of Nick's mother. Despite his initial reservations, Nick begins to bond with the baby.