Serena, Blair, Nate, Chuck and their class break into the school swimming pool for a night of fun, but when someone nearly dies, the school threatens to expel the person responsible for the break-in. Everyone agrees to not say anything, but this creates major problems between Serena and Dan. Vanessa, while working on a documentary project about private schools, accidentally captures Blair and Chuck discussing their affair. Lily tries to tell Rufus how she really feels about him.
Cyrus Lupo returns to New York after four years abroad to deal with his own terror. Lupo and Green investigate two suicides committed the same way. The detectives are suspicious of a parolee known as "Dr. Death".
Lupo and Green's first offical case together is a kidnapping that happened during a citywide blackout; a housekeeper is slain and a mother and daughter are kidnapped. The evidence that links all the kidnappers is the father and husband of the kidnap victims. When they search the kidnappers' hideout, they find preparations which implies that the kidnappers knew that the blackout was coming. Cutter must convince the man to testify after he has lied about a search warrant to save the man's daughter, or else the kidnappers will all go free. Issues of a warrantless search arise. Courtroom scenes revolve around questions of Enron-like manipulation of energy.
Calvin tries to prove his worth to Tracie, but she responds with shocking news. Meanwhile, Jazmine is plagued with a toothache, but it's like pulling teeth trying to get her to see a dentist.
When his crew departs on a call, Curtis is left alone at the firehouse with a pregnant woman who's about to give birth. Meanwhile, Tracie questions Calvin's maturity level, causing their relationship to wilt.
