Assigned with the task of protecting a valuable witness, Danko and the Officers must exercise caution regarding visitors to the prison. When a professional killer disguises himself as a professor seeing to interview Sol (the witness), Danko denies him the opportunity. Nevertheless, Danko does agree to help the 'professor' by accompanying him to an aircraft hanger where he claims he is meeting a friend. At the hanger, the killer reveals his true intention: to force Danko to wear deadly explosives while he holds the trigger, forcing the Police Force to negotiate Sol. Both Sol and the police refuse to compromise until a visit from Jill ultimately convinces Sol to help out. The Squad devises a plan that appears favorable to the killer but actually leads to his murder and Danko's safe release.

The Rookies must find those responsible for holding up gun shops throughout the city.