Is Mr. Sinister going to be the big villain in the X-Force movie? At the moment, there is no official indication that's going to be the case, but there is a reasonable amount of circumstantial evidence that may lead us to that conclusion. If not in X-Force, it seems like the recent X-Men movies have been signaling that the beloved villain will be making his way to that universe sooner rather than later.
Warning: This article contains spoilers for Deadpool 2. The trail of breadcrumbs we have to follow in order to get to Mr. Sinister, aka Nathaniel Essex, starts with X-Men: Apocalypse. To be a little more specific, the post-credits scene from that movie. Following Wolverine's rampage at the secret facility he is busted out of, an awful lot of blood is left behind in his wake. During the post-credits scene, strange men are seen collecting this blood who work for a place called Essex Corp, as indicated by the briefcase that they store the vials of blood in. Essex Corp, as in Nathaniel Essex, the man who eventually becomes Mr. Sinister.
There were rumors that Mr. Sinister was going to appear in Logan, but that turned out to not be the case. So what was this post-credits scene setting up? As it happens, Essex was named-dropped in Deadpool 2. The name Essex appears on the orphanage for mutants that Julian Dennison's Russell was living at and tortured in prior to the events of the movie. Nobody says Nathaniel Essex or drops Mr. Sinister in there, but the fact that the character's last name has appeared in two of the recent X-Men movies can't be coincidental.
Just for a bit of Marvel Comics history, Nathaniel Essex was born in London and is very old, dating back to the 18th century. He is a genetically altered human, similar to those in the Weapon X program. These alterations gave him superhuman, physical and mental abilities. Mr. Sinister is telepathic, able to manipulate minds and is capable of energy projection, via telekinesis. He's got a big bag of tricks. He is also a very twisted and has experimented on and tortured mutants over the years. He's obsessed with the idea of evolution and predicted the rise of mutants long before it actually happened.
Mr. Sinister is also one of the last huge X-Men villains that hasn't appeared on the big screen. There were rumors that he was going to be in the Gambit movie, possibly to be played by Daniel Craig, but that doesn't appear as though it's going to pan out. There were also rumors that a post-credits scene was shot for New Mutants that included Jon Hamm as Mr. Sinister, but that has reportedly been scrapped. And, not for nothing, but there are also rumors that Jessica Chastain is playing Miss Sinister in X-Men: Dark Phoenix. Could it be because Ryan Reynolds and director Drew Goddard have decided that Sinister is going to be the big bad in the X-Force movie? We've got just enough evidence in front of us to think that may well be the case. This was previously reported by CinemaBlend.