Robert Pattinson loves the challenge of breaking down walls through his acting.

In an interview that will be aired on Sunday (20Aug17) in the U.S., Robert told CBS Sunday Morning presenter Michelle Miller that he believes his job allows him to be whoever he wants to be.

"I think so much of life people are trying to put you in a box and define you all the time," he mused. "And it's just exciting to have a job where you're allowed to consistently break the walls of the box around you."

But the Twilight star also confessed that he struggles to land blockbuster roles because he's not a big enough star.

"It's not like: "Oh, I'll come down from an ivory tower to be...." he added.

"I mean, these roles are hard for me to get; it's not like I'm, like, Leonardo (DiCaprio) or something."

However, Robert isn't too worried about being cast in huge action movies because his level of fame does have its benefit when it comes to acting in the low budget movies he feels so passionately about.

''The only thing that being famous really helps in is getting financing for your movies," he smiled, admitting the films he loves to star in are "weird" and don't "make a lot of money a lot of the time."

Robert has been hitting headlines frequently since first finding fame in the Twilight franchise and dating co-star Kristen Stewart. But while he still struggles with the concept of being in the spotlight, the 31-year-old actor does feel privileged to be able to do a job he loves, although he does fear that it could all come to an end at any point.

"I always think that at some point karma is like, 'Oh, that's all, your luck's run out', so a whole bunch of bad stuff's gonna happen!"' he laughed.