Who plays Ladypool in 'Deadpool & Wolverine'? Everything to know about the A-list cameo

• A female variant of Deadpool appears during an action sequence in "Deadpool & Wolverine."
• The character, named Ladypool, is played by a well-known actor.
• Here's what to know about the cameo.

Warning: Major spoilers ahead for "Deadpool & Wolverine."

Ladypool — aka Lady Deadpool — has finally been unmasked.

The character is one of many variants of Deadpool that appear in Marvel's "Deadpool & Wolverine," which stars Ryan Reynolds as the Merc with a Mouth and Hugh Jackman as Wolverine.

During a major action sequence in the film, the titular characters fight 100 versions of Deadpool, including Ladypool.

Here's what to know about the cameo and the actor behind the mask.

Blake Lively plays Ladypool

The titular duo encounter Deadpool variants when they're sent to The Void, a metaphysical junkyard where the TVA sends people they want to dispose of. Deadpool and Wolverine first meet Dogpool, a dog variant, and her extra-kind owner, Nicepool (played by Reynolds), in The Void.

When Deadpool returns to his universe via a portal, the variants, collectively known as Deadpool Corps, follow him and start attacking. Ladypool leads the pack, which includes Babypool, Kidpool, Headpool, and Cowboypool.

Deadpool and Wolverine fight the Deadpool Corps to the tune of Madonna's "Like a Prayer." They only stop once Deadpool's friend named Peter (Rob Delaney) arrives in a Deadpool costume. Apparently, Deadpool has a Peter in every universe, and he's beloved. The variants quickly abandon their fight and gather to embrace — giving Deadpool and Wolverine the perfect opening to escape and focus on their mission.

Lively has a few lines during her cameo but never takes off her mask to reveal her face. However, she's listed as Ladypool in the film credits. She's not the only member of Reynolds' family who plays a Deadpool variant: Babypool and Kidpool are played by Lively and Reynolds' daughters Olin and Inez, respectively. Their eldest daughter, James, also has a small role as a screaming mutant.

Fans suspected that Lively was Ladypool before 'Deadpool & Wolverine' hit theaters

The identity of Lady Deadpool, a character from the comics with blonde hair and blue eyes, had been a mystery prior to the release of "Deadpool & Wolverine." The final trailer gave fans a proper glimpse of Ladypool, showing her head-to-toe costume and long, high ponytail.

Fan theories on her identity ran the gamut, from Lively and Taylor Swift (who no, isn't in the film) to Reynolds himself.

Reynolds commented on the speculation during a recent virtual press conference attended by Business Insider.

When asked about his favorite fan theory, Jackman said, "I like the one where Ryan is playing Lady Deadpool. Take the mask off!"

"As if I could..." Reynolds chimed in.

"My hips, they lie like hell. Those hips don't lie. Oh yeah, I was on set with her and she's... That is a red jaguar coming at us," Reynolds added, stopping himself before spilling any other hints.

Reynolds and Lively have been married since 2012, and she has blonde hair, so fans were convinced that she was playing Ladypool. Plus, she visited the "Deadpool & Wolverine" set, so it seemed like a no-brainer for her to appear in the film.

Speculation ramped up on Monday when Lively showed up to the New York City premiere of "Deadpool & Wolverine" wearing her hair in a high ponytail and dressed in a red custom Versace bodysuit reminiscent of Ladypool's outfit.

That day, Lively also shared a video montage of scenes from the "Deadpool" movies that were inspired by millennial pop culture icons, from Avril Lavigne and *NSYNC to "Frozen" and "Harry Potter."

"Tell me Deadpool's married to a millennial girl in real life without telling me," she said in a video posted on Instagram, which featured a montage of pop culture references.

"It's hard not to encourage my ladies to spot all the ways we've influenced @deadpoolmovie I've never been more proud. And I've given birth 4 times. 🤣" she captioned the post.