The 38-year-old actor couldn't stop gushing over his co-star while chatting with ET on Friday.
Matt Bomer is beyond excited to see Lady Gaga on the big screen.
ET caught up with the 38-year-old actor at a benefit for the onePULSE Foundation at NeueHouse in Los Angeles on Friday, where he praised his American Horror Story: Hotel co-star for her upcoming role in A Star is Born opposite Bradley Cooper.
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"That's fantastic!" he exclaimed to ET's Denny Directo, gushing over news that the singer landed her first lead role in a feature film. "She is gonna SLAY that!"
Following months of rumors that Gaga would be starring in the film about an aspiring actress who meets and falls in love with a movie star on the decline, her casting was finally confirmed earlier this week. In addition to acting, she'll be lending her songwriting expertise to the movie, which also marks Cooper's directorial debut.
"I'm excited," Bomer added. "I'll be there opening night, front row, popcorn ready."
As for the new season of AHS? Bomer claims he knows "nothing."
"Truly I know nothing. We'll see," he said. "When [show creator] Ryan Murphy calls, I say yes. That's my game plan. That's my MO. That's how I roll."
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Back in the day, before he was allowed to legally drink, Bomer used to roll to the bars with a fake I.D. When ET asked him if he remembered his first-ever gay club experience, he laughed and fessed up to the crime.
"Yeah I do [remember]," he said. "I think I snuck in underage with a friend actually. I used my brothers I.D. and got in."
"I wasn't 21 yet," he continued. "This was in Houston [Texas]. I don't remember the name of it though."
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Bomer joined the likes of Lance Bass, JC Chasez, Caitlyn Jenner, Jessie J and Stevie Wonder at Friday's star-studded ceremony, which was a benefit for the 49 victims of the June shooting at Pulse Nightclub in Orlando.
"I think it's just important to come out and let them know we care," he said, speaking to the friends and families of the victims. "That we, the Hollywood community, care about what they went through, and that we support them and continue to raise awareness and raise funds through the text to give."
You can donate to the onePULSE Foundation by texting 'PULSE' to 91999. The foundation will donate 90 percent of its proceeds to the families of the Pulse nightclub shooting.
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