Mary McDonnell Mary McDonnell

A potential rift in the LAPD emerges on Monday's Major Crimes summer finale.

While investigating the disappearance of several young women from a nightclub, Capt. Raydor (Mary McDonnell) and Major Crimes will butt heads with Special Operations Bureau No. 2 Ann McGinnis (guest star Laurie Holden).

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As you can see in the exclusive clip below, McGinnis has a personal stake in the case: One of the abducted young women is actually an undercover cop. But even though McGinnis wants to make this knowledge public, Raydor & Co. feel it would jeopardize the case and the lives of the other girls.

So, whose side is Chief Taylor (Robert Gossett) on? Click play below to find out whom he orders to "stand down."

Major Crimes airs Monday at 9/8c on TNT.