[s3e15] Mona-mania! Instant

The episode is often highlighted in rewatch discussions for its high-stakes intellectual battle and the deepening of the "Toby is A" storyline.

The central conflict is a "Quiz-Off" between Spencer and Mona for the team captaincy. Despite Spencer's early lead, she "chokes" on the final question regarding the dissolution of the Soviet Union, allowing Mona to win. [S3E15] Mona-Mania!

Aria discovers pages from Alison’s diary are missing from her hiding spot (her boots). She begins to suspect her father, Byron Montgomery , of being involved in Alison's disappearance, especially after seeing him act aggressively toward Meredith . The episode is often highlighted in rewatch discussions