In the fourth season 's mid-season finale "Now You See Me, Now You Do n't '', the Liars head to Ravenswood to look for Red Coat. While there, Red Coat kidnaps Emily and locks her in a coffin on a Sawmill. The Liars witness Red Coat heading to that Sawmill and chase her inside, where she actually stops the saw and another Red Coat, donning a mask of Alison 's face, appears on the stairwell, revealing that two people have been sporting the disguise all along. Spencer follows the "good '' one, while Aria fights and unmasks the other figure as CeCe Drake. The Liars manage to catch the "good '' Red Coat near the ending of "Grave New World '', who reveals herself as an alive Alison. During "EscApe from New York '', Ali claims that she asked CeCe to wear the disguise to distract "Big A ''. It is later revealed this was all a ruse, given that CeCe actually was the Red Coat who stole the game from Mona and wore the disguise during her schemes until she was caught in it. In "Game Over, Charles '', the Liars learn there was a third Red Coat who posed as a decoy to CeCe and used the infamous disguise to distract the Liars whenever she could n't. The third Red Coat is revealed to be Sara Harvey.
when do they find out who red coat is
the fourth season 's mid-season finale "Now You See Me, Now You Do n't ''