Robert Downey Jr has described Avengers Assemble as s 'complicated pregnancy'.
The actor reprises the role of Tony Stark this week as a whole host of Marvel heroes are brought together to save the world.
Downey Jr admits that different actors were in an out of the set as they pieced this movie of many strands and storylines together.
Speaking to Fox News the actor said: "It was like a complicated pregnancy.
"What was fun, this bit of WWE superhero tag-team wrestling, is where [Chris] Hemsworth's all beat up and he's been shooting nights, and my character's got the helmet closed, so I'm not there," he continued.
"Then he's flying home to be with the missus, and I'm coming in to do a bunch of scenes with [Mark] Ruffalo. I think everybody really bought into the spirit of the thing."
Downey Jr will be joined on the big screen by Hemsworth, Ruffalo, Chris Evans, Jeremy Renner, Scarlett Johansson, Samuel L. Jackson and Tom Hiddleston.
Avengers Assemble is out now.