The Professor is the main antagonist of Pretty Little Liars: The Perfectionists.
Nolan Hotchkiss meets this figure on the roof. He apologizes for his previous actions to them and informs them that his sister Taylor is alive. He then asks for the figures help. As the figure approaches him, a shocked expression comes across his face and he is thrown from the roof and onto the spiked fence below.
Later, the Professor hides amongst the crowd at Nolan's vigil and whispers to the Liars that his death was just like they planned it.
The Perfectionists later nickname them the "Pig Man".
- The Professor's tactics are similar to "A". This prompts the Perfectionists to nickname them "A" upon learning of "A".
- The Professor was initially presumably the same person who murdered Nolan Hotchkiss, though this is unconfirmed. The Professor later confirmed that they were indeed responsible.
- I. Marlene King has confirmed that she has already planned their identity.
- A fan jokingly noted that since Pretty Little Liars had "A" and "A.D.", Pretty Little Liars: The Perfectionists would have "B" and "B.C.", to which I. Marlene King replied "Well sort of." with a kissing emoji.