Plot summary
A young woman, Vanessa Nikos ( Karen Zippler ) is shot during an apparent holdup at a jewelry store but survives long enough to become an organ donor. Goren and Eames track down her killer and potential lung transplant candidate, Jesse Aparicio ( Luis Caballero ) but find him shot dead. Further investigation leads them to compulsive living donor Boyce Wainwright ( Gregg Edelman ) who originally donated a kidney to Nikos and has donated other organs to people he considers worthy recipients. The detectives surmise that he had promised a lung to Aparicio in order to convince him to mortally wound Nikos whom Wainwright thought was no longer worthy of his kidney and then killed Aparicio to silence him. Wainwright only admits his guilt when A.D.A. Ron Carver promises that he can continue to donate body parts while in prison.
Credits
Adapted from Wikipedia contributors, Law & Order: Criminal Intent season 4. HTML formatting and reference markers removed.