The truth about Jenna's blindness is eventually revealed as part of the show's central mystery, involving a series of threatening messages and stalking incidents from an anonymous sender known as "A." Here is what happens:
1. The Prank: It is discovered that Jenna was not actually blinded by the prank, which involved setting off fireworks near her face. Instead, she feigned blindness to cover up a different secret.
2. Revealing the Truth: Toby Cavanaugh, a police officer, reveals that he was the one behind the prank and that Jenna was not harmed by it. He admits that he pulled the prank to distract people from the real secret.
3. The Real Secret: The real secret involves Jenna and Toby's stepsister, Alison DiLaurentis, who disappeared before the start of the show. It turns out that Jenna was involved in a romantic relationship with Alison's older brother, Jason DiLaurentis, and Toby was upset by this.
4. Jenna and Alison's Relationship: It is revealed that Jenna and Alison were close friends, and Jenna shared personal secrets with Alison. In order to protect these secrets, Jenna pretended to be blind so no one would suspect the true nature of her relationship with Alison.
Throughout the series, Jenna becomes embroiled in the "A" mystery as she is connected to several characters and secrets in Rosewood. Her involvement adds layers of complexity to the overall plot, as she tries to navigate her own secrets while dealing with the Liars and the threats from "A."