Diagnosis Murder S08E07 - Hot House

One of Mark's med students, Alex, is a contestant on a Big Brother type reality show, hoping to win the grand prize so he can use it to pay off his student loans. When a fellow contestant ends up murdered, Mark takes the victim's spot on the show, with the hopes to find out the killer, he finds out the real reason why the contestant was targeted and how the killer almost got away with their crime.