A northern California marijuana mastermind cannot testify without using the drug to neutralize his anxiety disorder.

Mary briefs a new witness whose visitation rights with his son depend on the man's testimony. When Mary learns the boy is missing, she tries to find him.

Mary's paranoid witness wants to reconnect with his son.

Mary is caught between a witness and a suspect.

Mary plays marriage councilor in order to mediate a WITSEC divorce. Not only must she reconcile a stubborn witness, but also thousands of years of Hindu tradition, in order to save the case and keep a family out of danger.

Mary helps protect a guilt-ridden Army veteran; Marshall & Abigail consider the next step.

Mary sees whether she can balance motherhood with a demanding profession and a dysfunctional home life, or if she will put her baby up for adoption.

With Jinx out of town and Mark busy with a last minute business trip, Mary has no choice but to head to work with Norah in tow. But when Mary arrives, Delia points out the obvious: Mary can't be with Norah and a witness at the same time. Meanwhile, Marshall and Abigail are trying to determine whether or not Kristi Owens should enter WITSEC and Associate Director Campbell gives Stan some surprising news about the future of the Albuquerque office.

Mary protects a bigamist not only from his former employer, but also his two wives. In WITSEC, cheating the black market can be dangerous; but cheating on multiple wives is a death sentence.

Series Finale: Drastic changes take place at the Albuquerque WITSEC office. Mary finds herself caught between a witness and an unexpected family reunion.