And although they had only performed Shallow together outside of A Star Is Born on one other occasion, Gaga and Bradley truly brought the chemistry to the stage that landed both of them nominations for their acting at this year's Oscars.
At Gaga's crescendo, Cooper rose, moved his microphone stand behind the piano, and sat beside Gaga and sang over her shoulder into a single mic.
Lady Gaga won Best Original Song Oscar for Shallow.
While the HBO show is nothing to be sniffed at, Bradley, 44, had a small part in the show - a contrast to performing with Lady Gaga at the Oscars on Sunday night.
In the initial moments of her acceptance speech, an emotional Gaga spoke with a staccato with tears streaming down her face and thanked the Academy, Ronson and Wyatt, her sister and her family.
On the red carpet, top five most talked-about Oscars fashion looks on Facebook were: Billy Porter wearing a Christian Siriano tuxedo dress; Jason Momoa's pink velvet tux and matching scrunchie; Jennifer Lopez's mirror-mosaic gown; Lady Gaga's 128-carat Tiffany diamond necklace; and Spike Lee's custom metallic-gold Jordan 3 sneakers.
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Asked to clarify if he was considering calling for another referendum, Corbyn said: "That's the point we're discussing now in the party".
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While attending Elton John's Oscars party Sunday night, "The Hills" alum told US Weekly he feels "bad" for Khloe . Jordyn apparently left the party in tears after being told that she had kissed Tristan, the source claimed.
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The "Love Story" singer helped one of her biggest fans surprise his boyfriend after he proposed to him this weekend. Swift played an acoustic version of " King Of My Heart " from her latest album, Reputation .
"I think when you're in the room with this person, you don't have to do too much". Thank you for believing in us.
'There's a discipline for passion, and it's not about how many times you get rejected or you fall down or beaten up, it's about how many times you stand up and are fearless.
She continued, "I've worked hard for a long time, and it's not about, you know, it's not about winning".
Gaga made history at the 91st Academy Awards as the first person to ever receive a nomination for Best Actress and Best Original Song in the same year.