Danny and Jackie investigate a serial killer who is targeting prostitutes. Despite Danny's reluctance, Jackie goes undercover as bait to lure the killer. Jackie finds herself in danger when the serial killer turns out to be an unlikely suspect, and Danny must race to save her before she becomes the next victim. Meanwhile, Frank works with the union president to eliminate non-essential department spending, but the man proves unwilling to make concessions. While Henry organizes the Police Sports League, he runs into an old friend who offers him a job working at a private security consultant agency, but it turns out to be a ruse to gain the union better access to Frank. Erin hopes to deter Nicky from a law enforcement career by immersing her in the arts, but instead ends up on a date with the charming Jacob Krystal, an art appraiser who's full of alluring secrets.