Robert Pattinson Says His Batman Performance Made Girlfriend Suki Waterhouse Cry: 'She Held My Hand'

Robert Pattinson got approval for his Batman role from one of the people who matters most: girlfriend Suki Waterhouse.

Pattinson, 35, who appeared on Jimmy Kimmel Live Wednesday, recalled the first time seeing himself in the upcoming Batman movie ahead of the film's premiere next month. The actor, who plays Bruce Wayne/Batman in The Batman, told host Jimmy Kimmel that he was "scared" to release the film, but was reassured by Waterhouse, 30.

"I was absolutely terrified," he said. "I haven't been this scared to release a movie in such a long time."

Before attending a screening with Waterhouse and director Matthew Reeves and his family, Pattinson told Kimmel he had to get in the right headspace.

"I need to be in the perfect balance of serotonin to watch my own stuff," he explained. "I need to workout for two hours before, and I need to have an enormous amount of sugar and caffeine. So whenever I'm watching, I'm like, 'Yes!' "

Despite his fear about watching his own work, Pattinson said Waterhouse's reaction to The Batman "kind of changed the entire thing."

"I'm pretty sure she's not normally into watching superhero movies," he said. "And just seeing that it was capturing her attention the entire time, and then she held my hand and touched it [to her face] and I could feel a little tear. And I was like, 'No way!' "

Pattinson and Waterhouse have been dating since July 2018. A source confirmed their relationship to PEOPLE after the two were spotted at a screening of Mamma Mia! Here We Go Again in London.

The actor opened up about his relationship with Waterhouse in a GQ cover profile for the magazine's March 2022 issue, recalling a moment when Waterhouse chatted with a boiler repairman at his home about DC comics.

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"He just randomly started talking about what a DC fan he is. And I'm sitting there facing the other direction, and my girlfriend just keeps continuing the conversation with him," Pattinson told the magazine.

"And I'm looking at her like: 'Shut the f--- up!' " he added with a laugh. "'Why are you doing this to me?' She was very entertaining. Just talking to an obsessive fan."

The Batman premieres in theaters March 4.