Bradley Cooper and Lady Gaga during the 25th Screen Actors Guild Awards at the Los Angeles Shrine Auditorium and Expo Hall on Sunday, Jan. 27, 2019. Image Credit: TNS

Actor-director Bradley Cooper made a surprise appearance at Lady Gaga’s show in Las Vegas.

The crowd at Las Vegas’ Park Theater was treated to Cooper’s surprise appearance during Gaga’s finale performance of the song ‘Shallow’, from the soundtrack of ‘A Star Is Born’, according to the Hollywood Reporter.

The song, which was nominated for an Academy Award earlier this week, is the closing number of the ‘Enigma’ show, the residency that kicked off in December last year.

Attendees had no idea a duet was in store when the actor appeared on stage. The two embraced and he followed Gaga to the piano.

“I even got you in ears,” Gaga told Cooper of the monitors used during live stage performances.

“I can’t hear anything,” he cracked.

Following the performance, as each of Gaga’s dancers took a bow and introduced themselves, Cooper shyly joined in and said: “Bradley, thank you.”

He then pitched his baseball cap into the crowd.

‘Shallow’ is set to be performed at the Academy Awards on February 25, reported Variety.