Law & Order: Criminal Intent S07E09 - Untethered

A young prison inmate is killed in an upstate New York facility's mental ward. Detective Robert Goren's nephew Donny, an inmate in the same prison, tells Goren he thinks the prisoner was murdered, Goren goes undercover. In order to determine if a crime was indeed committed, Goren manipulates his way into the same mental ward to either prove or refute his nephew's claims.