Kristen Stewart has said that of her body of work, which spans upwards of 50 credits, only five films are “really good.”

The actor reflected upon her career to date while promoting her upcoming film Spencer, a historical drama about Princess Diana in which she takes the lead.

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“I’ve probably made five really good films out of 45 or 50 films?” she told the Sunday Times. “Ones that I go, ‘Wow, that person made a top-to-bottom beautiful piece of work!’”

Stewart went on to say that while she didn’t regret the result of making the other films, she took issue with starting work on a project only to discover that “it wasn’t fun.”

“The worst is when you’re in the middle of something and know that not only is it probably going to be a bad movie but we’re all bracing until the end,” she explained.

She continued: “It’s like starting to date someone and going, ‘Woah! I don’t know what we’re doing!’ But when you’re in the middle of a movie you can’t just break up.”

Although Stewart declined to comment on which films she was referring to – “I’m not a mean person”, she said – she did cite filmmaker Olivier Assayas as one of her favourite collaborators.

“I love Assayas’ movies,” she said. The pair worked together on Personal Shopper and Clouds Of Sils Maria, which earned her the French equivalent of an Oscar.

Elsewhere, Stewart has responded to a social media campaign which is calling for her to be cast as the Joker opposite Robert Pattinson‘s Batman.

Speaking to Variety, Stewart said: “I love the energy behind that. It’s really been done so well.

“I feel like, maybe, we don’t traipse over, but I love that gusto. Let’s figure something else out. I’m totally down to play a freaky, scary person.”