Three Wives, One Husband (2017)

S4E10 The Thing About Heroes

Title: The Thing About Heroes Plot: During his time in Chicago, Mac stumbles upon additional evidence related to his stalker, shedding light on his complicated history. Back in New York, the rest of the team faces imminent peril. With the clock ticking, they race to uncover the identity of the mysterious 333 stalker before it's too late.