Robert Downey Jr. is taking ‘Iron Man 2′ more seriously than any other film of his entire career.

The 44-year-old actor - who plays industrialist Tony Stark and his metal-suited alter ego - is feeling the pressure on set because so many people enjoyed the first movie so much.

He said: “I’ve never been in a sequel and it’s very daunting because I feel the expectation of millions of people who watched the first film and enjoyed it. So I have probably taken ‘Iron Man 2′ more seriously than any other movie I’ve done. The fans are expecting us not to screw the next one up.”

Although Downey is feeling the pressure to make a great movie, he isn’t feeling uncomfortable in his superhero suit.

He added: “Everything has been improved with the suit. It’s all ergonomic. It’s great!”

Downey stars in the movie with Gwyneth Paltrow, who reprises her role as his assistant Pepper Potts, Scarlett Johansson - who plays Natasha Romanoff and her sexy alter-ego, Russian spy Black Widow - and Mickey Rourke, who plays super-villain Whiplash.

Samuel L. Jackson also features as super-spy Nick Fury.