Yet, the double, James, is annoyingly self-assured and confident, soon showing up Simon in the eyes of the boss and, worse yet, in the eyes of Hannah (Mia Wasikowska), the cute girl in the office Simon's been crushing on.
We develop underdog sympathies for Simon right off the bat. After all, who hasn't suddenly been confronted with a rival and wondered, what's he got that I haven't?
But as the film goes on, James becomes increasingly more sinister in Simon's eyes. And we wonder if Simon's losing it. If maybe he is James and if what we're seeing is one man's madness. That's the theme of the Dostyevsky story the film is based on, and it reels us in, aided by fine performance by Eisenberg in both roles and direction and staging that gives everything an alien, yet familiar tinge.
Simon's workplace is depressingly bleak, filled with outdated-looking yet strangely different technology. Apart from James and Hannah, all his co-workers seem to be elderly. There's an "Eraser Head"-like dream/nightmare feel to it all. The absurdity of his surroundings and circumstances make us laugh, but there's plenty of darkness here, too.
The parallels of the film to the other recent suddenly-I-have-a-double film, "Enemy," are interesting. While that film was darker and more suspenseful than this one, they both hit many of the same sinister notes. Turns out one of the things that can frighten us most is ourselves.
X-Men: Days of Future Past. Loosely based on the 1980s comics storyline by Chris Claremont and John Byrne, this is a film that can't really stand alone. You need to have seen all the previous X-Men films, plus the Wolverine films to fully engage with the characters and plot.
Which, I suppose, isn't necessarily a bad thing. It's more an indication of how increasingly similar watching superhero movies on screen has become to reading comics. Marvel has created an on-screen Universe -- actually a few of them -- that has become increasingly self-referential. That can shut out newcomers and result in plots that rely more on playing with the pieces than originality. But it also can result in longer, more-sophisticated stories that get told over multiple films, not just one two-hour adventure, and which help us get to know the characters better.
That aspect is nice here, as we spend most of the film with just a handful of characters: Wolverine and the younger "X-Men: First Class" versions of Professor X, young Magneto, Beast and Mystique. The rest of the gang is essentially relegated to cameo status.
Hugh Jackman's Wolverine is a blast here: Lots of funny bits, lots of action. The story sends him backward through time, to the early 1970s, so we get some funny period touches, too. James McEvoy is also very strong as the young Xavier - less stoic, more rebellious and lively than his older self.
The big lost opportunity, however, is Jennifer Lawrence as Mystigue. She has plenty of shape-shifting action scenes, but not nearly enough quiet time. We can't fully appreciate and sympathize with the actions she takes to lash out at humankind on behalf of persecuted humans. As one of our best young actresses, Lawrence is more than capable of bringing some real "humanity" to this blue-skinned mutant, but the screenwriters never give her a chance.