Nash and Joe meet Caitlin for breakfast to discuss a missing cadaver that Nash has absconded. Two men observe in a car - one (armed with a silenced gun) gets out and walks towards Caitlin. A bicyclist rides by the car and plants a bomb on its side. The car blows up, knocking over the assassin before he can get to Caitlin.
The blown up car was registered to a James White of a bogus company named Far East Imports. The bomb was sophisticated with no traceable elements. Nash suspects professional spies. FBI agent Richard Langdon shows up, revealing that Caitlin is suspected of killing Jeff Maschino in retaliation for Maschino killing her partner Tim McDonald. Agent Langdon searches Caitlin's apartment. Caitlin calls in her former CIA boss, Elliot Rand. Rand agrees to meet her in six hours, but Caitlin must avoid the presumed-to-be-dead assassin Maschino.
Joe is scheduled by wife Inger with a trainer to get Joe in shape. Joe expects to gets lovely Anna as a trainer, but is instead assigned to Udo, Anna's husband. Nick's ball room dancing partner Jillian is injured, so grand daughter Cassidy volunteers to fill her place for a dancing competition.
Evan and Harvey continue to find out nothing about the mysterious Maschino. Harvey brings in a digital camcorder to record the mysterious disco outbursts in the new SIU barge to prove that they do occur. Harvey takes a tumble down the SIU stairwell trying to get to the camcorder, only to be too late as the disco eruption disappears once again.
Caitlin meets with Elliot - he offers her a new identity in Istanbul. Caitlin refuses; she goes back to her apartment to check on her room mate and finds Agent Langdon dead on her living room floor. Finally, she asks Nash for help. Nash hides Caitlin at the private detective agency office. Caitlin reveals to Nash that she has spent the last three years trying to clear her partner/lover Tim McDonald's name. They are both suspected of passing secrets to the Russians.
The autopsy of Agent Langdon points neatly to Caitlin. The FBI agent is shot with Caitlin's gun with her fingerprints on the gun. Langdon has all of Caitlin's case files which Nash examines. Nash gives Caitlin a clue - the suspect was code named DANCER. Nash meets with Elliot Rand, but Elliot reveals that he also suspects Caitlin of being a traitor.
Caitlin figures out the clue - DANCER is an anagram for EC Rand. Eluding the protection of Evan and Harvey, Caitlin goes to confront Elliot Rand. Rand confuses Caitlin even more by revealing that he loves her, but he is the traitor. Maschino shows up and immediately kills Rand. Maschino reveals that it is Rand that killed Tim McDonald to cover his own crime. Nash and the SIU intervene to save Caitlin before Maschino can kill her.
An exhausted and suffering Joe quits his exercise regimen and fires the trainer. Nick and Cassidy don't win the dancing competition, but Nash is proud of Cassidy nonetheless. Caitlin calls Nash on his car phone, but she is unable to utter a word of thanks, but Nash guesses it is Caitlin.
For more, see commentary for Episode 65