Nick is murdered in his condo and Natalia is arrested for the crime when evidence at the scene suggests she killed him, but Horatio tries to clear her name. The evidence also reveals that Delko and Nick fought earlier in the day. In another case, a wealthy single man is found dead in his mansion with a granite-topped bookshelf on top of him. The investigation reveals the victim was seeing a therapist who suddenly dropped him as a patient. It is suddenly discovered, that the two cases are related.

The lives of two CSIs are put in danger when an old enemy of Horatio's returns. When a truck full of confiscated weapons is hijacked and the weapons are released back into the public, Horatio links the crime to Clavo Cruz, a man he put away for murder years ago. However, on the day of Clavo's arraignment, a confiscated missile is launched into the courthouse to aid his escape, with Alexx inside. Meanwhile, Calleigh and Ryan investigates when an eleven-year-old boy is shot by one of the stolen weapons. The episode ends with the shocking revelation that Delko has been shot in the head.