The actor - who plays the titular fictional detective in 'Sherlock Holmes' and inventor-turned-superhero Tony Stark in 'Iron Man' - loved his experiences on the set of both films so much, he wants to keep returning for new installments until he is forced to quit.
He said: "I'd be happy to bounce back and forth between Sherlock and Tony Stark until I'm forcibly retired.
"And fortunately, not unlike Iron Man, there is a way to continue along the lines of Sherlock and not become embarrassed by my greying hair and more ropey muscles."
Robert's 'Sherlock Holmes' co-star Jude Law also revealed he is hoping to get cast in a sequel to the detective adventure.
He added to Empire magazine: "We would love the audience to fall in love with it as much as we have so we can tell a whole bunch more." (C) BANG Media International