Molly and J.D. discover another pregnant woman who is suffering from inexplicable and fatal symptoms. Meanwhile, Molly begins to question her own mental stability. Julie struggles with Ethan's rebellion.

Molly finally learns the frightening truth about what happened to her son. Also, Julie’s decision to erase Ethan’s memory has disturbing consequences.

Molly discovers Ethan is alive and sets out to get her son back. Also, suspicions about John’s death cause JD to investigate Julie’s potential involvement.

Molly panics when she discovers she is changing physically – the question is into what, and whether she can reverse what’s happening to her. Also, JD’s ex-wife, Dorothy, shows up suddenly on his doorstep to discuss their daughter.

Molly and JD try to convince Shepherd to broker a peace between humans and hybrids. Meanwhile, Lucy tries to manipulate Charlie’s feelings to put him in a compromising position.