The stranger strikes again — this time, with a blackmail ploy. Corinne won't return Adam's calls. The kids scramble to cover their tracks.

While the police question Mike, Daisy makes a confession to Thomas. Adam's search for clues about Corinne leads him to another victim of the stranger.

The boys make a discovery that sets Adam on Corinne's trail — and dredges up an old secret of his own. Kimberly gives Johanna a lead about Heidi.

Adam tells Johanna about his encounter with the stranger. The kids spy on Olivia's house. Martin's appeals finally run out.

A shocking confession sends Adam reeling. Armed with new information, Johanna sets up a meeting — putting Katz in the hot seat.

With help from an unlikely ally, Adam uncovers a startling secret. Backed into a corner, Katz makes a rash decision.

A violent confrontation leads to new revelations, and the truth about Corinne's disappearance finally emerges.