Marvel Studios is known for how well they tend to guard against spoilers, but Benedict Cumberbatch found himself breaking one of their cardinal rules.

The actor will reprise the role of Doctor Strange in Avengers: Infinity War, and from the looks of the trailers he will be heavily involved. As a result, of that heavy involvement, Cumberbatch got to do something most other Marvel actors never get the chance to do.

“Well, that’s a loaded question, because I’m not supposed to have read the script,” Cumberbatch told EW, "But I have. It’s just mind-blowingly epic. What I thought is, this just doesn’t stop. Once it starts, it does. Not. Stop. It’s just this horrible, brilliant, terrifying, at times funny, at times very moving, relentless action. It’s like everyone’s constantly in crisis, and catching up with themselves, and it’s really breathless to read a script like that. This isn’t a slow burn. You’re really thrown in helter-skelter. [Laughs] It’s got a lot of facets to it, but I think the main one for me was just how utterly relentless the events and action were.”

Marvel typically only lets their actors read their portions of the script to keep from having multiple copies of the full script out in the open. They made an exception for Cumberbatch though.

"Well, it’s not Marvel’s practice to hand around the whole script of any particular one of their enterprises, especially a film as big as this, and as secret as this," Cumberbatch said. "I kind of had to have a bit of an overview to understand what I was doing in it. Maybe I’m just a bit more stupid than the other actors involved. I just need a little bit of special care. And they were very sweet, and chained me to something immovable whilst I read it, and unchained me after I finished reading it."

As to what he will be doing in the film, well, he obviously can't spill the beans just yet.

"And this is where the interview gets dull! Because I can’t really say. [Laughs] He’s pretty actively involved, he’s got quite an important Infinity Stone that’s in his vicinity, and that draws him into the action, as well as a couple of other characters’ plights — and stuff happens. [Laughs] That’s about it! That’s about all I think I can say," Cumberbatch said.