“Pretty Little Liars” Cast Forgot Sydney Sweeney Made a Cameo in the Series Finale: 'Is This True?'

Ashley Benson, Troian Bellisario, Keegan Allen and Torrey DeVitto reacted to Syndey Sweeney's 2017 appearance on the hit Freeform series during their panel at Epic Cons Chicago

The cast of Pretty Little Liars couldn't recall a Euphoria star’s visit to Rosewood!

At the fan convention Epic Cons Chicago on Saturday, which PEOPLE attended, Pretty Little Liars cast members Ashley Benson, Troian Bellisario, Keegan Allen and Torrey DeVitto — who played Hannah Marin, Spencer Hastings, Toby Cavanaugh and Melissa Hastings, respectively — were shocked when asked about Sydney Sweeney’s appearance in the finale of the Freeform series.

“Is this true? Who does she play?” moderator Arielle Kebbel asked the crowd in footage captured by a fan, before jokingly adding, “She doesn’t have a name. No one cared about her back then. Got ya.”

Related: 'Pretty Little Liars' Cast: Where Are They Now?

“I’m in the Twilight Zone,” a shocked Devitto, 39, responded. “What?”

However, Allen, 34, was still in disbelief, saying, “I’m gonna look this up. This is blowing my mind.”

Sweeney played Willa, a high schooler who went missing, in the finale of the hit series in 2017. When fans asked what the purpose of Sweeney’s appearance, Devitto joked, “Well they didn’t even know she was in the show.”

“I think that’s probably Marlene [King] setting up the generation and when we ended our show, it wasn’t like it was going to be immediately spun off,” Bellisario explained. “I imagine that was her just saying, the story continues.”

Related: 10 Times the 'Pretty Little Liars' Cast's Friendship Made Our Hearts Melt

After discovering Sweeney, 26, did, in fact, appear on the show, Allen got up and paced back and forth on stage with hands on his head.

As she showed his phone to his former costars, Bellisario said, “I remember this” and he commented, “It’s f---ing her.”

He added: “Dude. What is the world, dude? Bro, bro.”

When asked if the spinoff series with Sweeney was not picked up, Bellisario clarified, “It wasn’t that just didn’t get picked up… We ended our show and there was no other intention of doing a spinoff yet so it was just kinda like Marlene’s way to be like this story could be continued, isn’t it fun? It’s happening all the time.”

Pretty Little Liars concluded with its seventh and final season in June 2017. The hit teen drama premiered in 2010 on ABC Family (now Freeform) and featured 160 episodes during its run.

The mystery series, helmed by I. Marlene King and inspired by the book series of the same name by Sara Shepard, followed a group of friends who were stalked by the elusive "A." While "A" begins to contact them following the disappearance of their friend Alison DiLaurentis (Sasha Pieterse) and they eventually unmask the culprit. However, the foursome learns throughout the show that the horrors haunting them are much deeper than they previously thought.

The show's popularity spawned multiple Freeform spinoffs, The Perfectionists and Ravenswood, as well as a reboot on Max centered around an all-new mystery, Pretty Little Liars: Original Sin. Original Sin premiered on Max in 2022 and is set to return for a second season.

Related: Ashley Benson and Husband Brandon Davis Welcome First Baby Together

Since going off the air, a handful of original cast members have reconnected at select events, including three out of the four Liars — Bellisario, Benson and Lucy Hale, 34 — who spent time together last year.

The three stepped out to attend the charity Every Day Action's casino night-themed gala in March 2023, where they posed together for a sweet photo.

Bellisario shared the shot on Instagram and captioned it, "mini reunion for an amazing cause." On Bellisario's post, the Pretty Little Liars creator commented with three red heart emojis.

Benson also posted a photo from the gala, writing, "My girls 🖤 last night," in the caption.

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Pretty Little Liars is available to stream in full on Max.

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