Caleb and Toby work together to investigate "A" and the incident involving the lodge fire. Meanwhile, Hanna tries to pretend that she's fine, but her pals worry about her; Aria finds Mike's behavior troubling; and Ezra's unsure of his role in Ari's life.

Paige throws Emily a surprise birthday party with unexpected guests: Jenna and Shana. Meanwhile, Mona helps out Hanna and Ashley; Ezra receives some upsetting news; and Emily meets with a prestigious swimming coach.