When a key suspect vanishes it casts an ominous shadow over the investigation. Questions quickly begin to circulate about whether their disappearance has a more sinister implication. PJ and Linus attempt to piece together what happened the day that Tommy Burke disappeared. In his attempt to help the suspect, PJ makes a dangerous decision that leaves him worrying his actions may have jeopardised the entire investigation. However, a startling breakthrough turns everything on its head and throws the entire case into doubt.