As it is, Deadpool 2 currently boasts a delightful ensemble cast of franchise favorites and newcomers -- but it sounds like the film will also include another major appearance.
The Hollywood Reporter covered the test screenings for Deadpool 2, in the wake of the film's recent reshoots in Vancouver. According to the report, these reshoots "also [included] two hours' worth of work recently in Los Angeles for a secret cameo."
While it sounds like this secret person wouldn't have too big of a role in the film - after all, two hours of work would probably result in a short scene or so of finished footage - this development is sure to make fans speculate.
So, who exactly could that secret cameo be? One easy assumption would be that it's Stan Lee, considering the Marvel icon's proclivity for cameo appearances. But for some fans, the possibility of Lee cameoing almost seemed expected, considering how much he enjoyed his appearance in the first Deadpool.
But there are quite a few interesting possibilities still within the Marvel realm. Another possibility could be Patrick Stewart, who stole everyone's hearts with his decades-long portrayal of Professor X. While Charles Xavier met his end in Logan, Stewart has previously expressed an interest in returning to the role only in the context of a Deadpool film.
"I would have said yes [to being done in the role]." Stewart said about a year ago. "But the discussion just now about Deadpool makes me think, well, maybe there is a proper justification for the revival of Charles Xavier."
Speaking of revivals, another guess about this secret Deadpool 2 cameo will surely center around Hugh Jackman. After Jackman and his role as Wolverine were mentioned quite a bit in the first Deadpool, fans wondered if there could be a meta way for Jackman to share the screen with Reynolds again in some way. Fans even floated around the possibility that he could appear as himself, something that even the film's writers have somewhat endorsed.
And even if Jackman isn't the mysterious cameo, there's still a chance that the appearance could have some Marvel actor in a meta context, one that references their role without being a direct crossover between the currently-separated franchises. But once you consider that, the possibilities venture off pretty wildly.
One potential version of that - and one that has jokingly been tossed around in the fandom for years - has been Andrew Garfield, who previously played Spider-Man in Sony's Amazing Spider-Man films. Now that Garfield isn't currently associated with the character, there could be a pretty clever way to go about that, subtly playing off of the fan-favorite "SpideyPool" dynamic (and real life, to an extent) without interfering with Tom Holland's current tenure as the web-slinger.
Or, perhaps the cameo is from another Marvel actor -- someone who is currently starring in the MCU. While that theoretically would be somewhat of a long shot (even with Josh Brolin doing double duty as Thanos and Cable), there could be some sort of argument for it, considering the one-two punch of the Disney/Fox deal and of Deadpool 2 and Avengers: Infinity War having release dates close together. But that would beg the question of exactly which Marvel star would be able to get away with a cameo like that, considering the somewhat protective way that Marvel Studios holds onto their actors.
So, who exactly could the secret cameo be? Honestly, it's too early to tell... but that probably won't stop fans from being eager to find out.