Nora and Saul's not-so-loving mother (Marion Ross) makes an unwelcome visit to celebrate a milestone in her daughter's life.
Darwyn strives to maintain his cover; Farik's interrogators utilize new techniques to get information.
Blaming himself for Gayle's death and Mina's successful suicide bomb attack, Darwyn embarks on a suicide mission of his own, heading to Yemen to seek out Farik one last time.
The cell hijacks a chemical truck; Farik spends the last night with his wife; the FBI prepares to stop the attack.
When Darwyn discovers that the explosion is a decoy, he leaves a clue he hopes will lead the FBI to the true target.