The girls are desperate for an invite to Noel Kahn’s legendary Halloween party.
The episode follows the Liars—Aria, Hanna, Spencer, and Emily—during the Halloween of 2008, when Alison DiLaurentis was still the undisputed "Queen Bee" of Rosewood. [S2E13] The First Secret
While shopping for costumes, Alison meets the "new girl," Jenna Marshall. When they both want the same Lady Gaga costume, Alison attempts to intimidate her, but Jenna famously refuses her offer of friendship, marking the start of their rivalry. The girls are desperate for an invite to
Discovers her father, Byron, having an affair with one of his students, Meredith, and is sworn to secrecy. When they both want the same Lady Gaga
Fans often cite this as a top-tier episode because it fills in essential gaps in the Rosewood lore. It highlights Alison’s manipulative nature and the complex power dynamics she held over her "friends," while also planting early clues about the and the identities of those who hated her most, such as Lucas and Mona. Pretty Little Liars S2.E13 “The First Secret”