Captain America: Civil War might just be the most exciting movie set in the Marvel Cinematic Universe to date. Pitting hero against hero, it will see Steve Rogers go to war with Iron Man over the Superhuman Registration Act. Little is known about the film at this early stage, but we know that Spider-Man will appear!

According to the official synopsis, Civil War picks up where Avengers: Age of Ultron left off, as Steve Rogers leads the new team of Avengers in their continued efforts to safeguard humanity. After another international incident involving the Avengers results in collateral damage, political pressure mounts to install a system of accountability and a governing body to determine when to enlist the services of the team. The new status quo fractures the Avengers while they try to protect the world from a new and nefarious villain.

One of the biggest mysteries is who Martin Freeman is going to play. Marvel didn’t reveal any character details when they announced his involvement, but the Sherlock star has now shed some light on his role.

“He works for the American government. He works in conjunction with the superheroes, and certain agencies that help to tame the superheroes’ power, I suppose. So you’re not quite sure which side he’s on. It looks a little bit like he’s playing one game when actually he’s playing another. It’s the kind of character I like because it’s ambiguous and because you don’t know whether he’s good or bad. I like that area that isn’t black or white, I like the greys, because I think there’s just more fun to be had in not playing one obvious line.”

It sounds like we’ll have to wait and see if he’s a good or bad guy then, and it’s going to be exciting to find out. There are a few different characters he could be playing from the comics, but as Marvel have a habit of taking fairly obscure supporting players and reconfiguring them for their movies, it’s hard to say who!