The accusations from fans that their on-screen chemistry couldn't have been faked were pervasive -- exacerbated by their undeniably steamy Oscars duet -- and their close friendship and beaming red carpet appearances added fuel to the fire.
Those rumors only got more persistent after Cooper and his girlfriend of four years, Irina Shayk -- with whom he shares a 2-year-old daughter named Lea -- called it quits earlier this month.
However, Gaga is far from the first of Cooper's co-stars with whom the charming, handsome star has radiated chemistry and a magnetic connection -- and the speculation about off-screen romances aren't new for the actor either. Here's a look back at all the times Cooper and his big screen co-stars shared seriously off-the-charts chemistry.
What They've Worked on Together: Silver Linings Playbook (2012), American Hustle (2013), Serena (2014), Joy (2015)
What They've Said About Each Other: Lawrence has never shied away from heaping praise on Cooper, especially considering the fact that they appeared together in three out of the four movies that earned her Academy Award nominations, and shared nearly every scene in Silver Linings Playbook, for which she actually won her Oscar.
The role also earned her the Critics' Choice Award for Best Actress in a Comedy, and she spoke fondly of Cooper in her acceptance speech, sharing, "Bradley, the first time we ever did a scene together, you took my breath away. And the first time that I saw the movie, you broke my heart and put it back together."
During a Cinema Society screening of their film Serena, Lawrence also said that Cooper set the standard and raised the bar for acting partners. "I forced him to come onto the movie. I mean, any male role is going to make me think of Bradley because, in my opinion, he's the best, and I love working with him."
One of the defining moments in their relationship, at least from Cooper's perspective, appears to be when they learned and performed the climactic ballroom dance scene in Silver Linings Playbook. Cooper said of the experience, "I wonder if these guys who do Dancing With the Stars, like, have a connection forever. I really do think that really provided the basis by which we can just work together. We don’t talk often, but when I showed up in Boston for Joy, then all of a sudden it was like we never stopped. We just started where we left off, and that’s rare. It’s just easy to look at her and feel like I’m telling the truth."
Cooper told Rolling Stone in 2012 that Lawrence is "the person you want on set with you at 4:00 in the morning when you're losing your mind." Speaking with Nightline in 2015, Cooper reiterated his thoughts on their instant chemistry and indelible friendship, explaining, "I feel very safe [with Lawrence]. I can turn my brain off as an actor."
Romance Rumors?: Given the number of projects they've worked on together, both Cooper and Lawrence have been asked about potential off-set chemistry many times, and they've both roundly rejected the suggestion. Cooper told Howard Stern in October 2015 that he "never" slept with his co-star, adding, "It just didn’t happen. It’s not the way we are together."
What They've Worked on Together:Alias (2001)
What They've Said About Each Other: After starring together for two seasons on the hit ABC spy thriller, the pair have remained friends, and Garner was tapped to introduce, and lovingly roast, Cooper at the American Cinematheque Awards in November 2018. Garner recalled how she was one of the first people to ever meet Cooper when he came to Hollywood and quipped about how she viewed him the same way she would a stray dog, joking, "I took him home and made him dinner… I’m still making him dinner."
"Bradley, what’s happening to you now is a pure joy to those who know you, especially to those of us who’ve known you from the start,” she added in her heartfelt speech to her longtime friend. "It turns out you weren’t just handsome all along. You were also a wonder, and you are welcome at my table anytime."
Cooper's actions speak louder than words when it comes to his relationship with Garner, even turning to her for advice on cooking when he starred as a professional chef in the 2015 drama Burnt. They were most recently spotted hanging out when Cooper and Shayk came over to Garner's house for dinner back in March.
Romance Rumors?: While the pair have stayed close, they've never been romantically linked as both stars rose to prominence.
What They've Worked on Together: He's Just Not That Into You (2009)
What They've Said About Each Other: Speaking with ET in February, Connelly looked back at their time on the set of He's Just Not That Into You -- in which she and Cooper played a married couple whose relationship falls apart after he cheats on her -- in honor of the film's 10th anniversary.
Reflecting on a famous scene in which Connelly's character trashes their home after discovering the infidelity, the actress said, "It was fun. I liked doing that scene… I had a good time. It was a nice group of people. I loved spending time with all the cast members, all the women. And Bradley was great."
She also had a lot of praise for his work behind the camera directing A Star Is Born, sharing, "He's super talented… I didn't know that he'd wind up being such a fantastic director [but] I thought he did a really wonderful job."
Romance Rumors?: Seeing how Connelly was (and still is) happily married to fellow actor Paul Bettany during production, she and Cooper were never romantically linked.
What They've Worked on Together: He's Just Not That Into You (2009)
What They've Said About Each Other: When the pair appeared together in the 2009 romantic dramedy, with Johansson playing the woman Cooper's character cheats on his wife with, both stars were in high-profile romances -- Johansson was married to Ryan Reynolds and Cooper was reportedly dating Renee Zellweger. However, in 2012, the two were romantically linked after their relationships fell apart, with some fans pointing to interviews Cooper and Johansson gave while promoting the film two years earlier that they claimed paralleled potential romantic feelings between the stars while on set.
"Even though someone was being hurt in the process, I don’t think my character was bad. I think the two characters really like each other. They connect…. She’s not looking to steal a married man. He’s not looking to have some affair. Both go into it knowing there is somebody else in the relationship that they really feel that this is the point in their life," Johansson said of their star-crossed characters. "I think you can’t hate them because they don’t go into it with malice. They don’t go into their relationship with a hope to hurt somebody. In life, things happen, don’t they?"
"I think it’s easy to vilify these characters, but it’s not in the writing. You feel sorry for them, the wreckage that he’s caused because he’s not a man," Cooper said of his character, Ben, who cheats on his wife, Janine (Connelly), after falling for Johnansson's Anna. "But, you can understand him."
Romance Rumors?: Cooper and Johansson were spotted enjoying a romantic dinner at a Bel-Air hot spot in June 2012, and Daily Mail reported that an eyewitness said their chemistry was "VERY evident."
"Bradley seemed almost distracted by Scarlett's beauty, especially since she was wearing a very low cut dress, and Scarlett was totally working her charms," a source alleged to Glamour magazine at the time, adding that they were "having more than a 'friends' dinner, it seemed pretty obvious they totally have the hots for each other."
The pair never commented on speculation that they'd sparked a romantic interest following their respective breakups and many fans of both actors believe that the former co-stars were simply enjoying the comfort of friendship following their high-profile splits.
What They've Worked on Together: Wedding Crashers (2005), Aloha (2015)
What They've Said About Each Other: McAdams has had nothing but love and praise for her co-star over the years, and shared some particularly kind words after they worked together on Cameron Crowe's 2015 rom-com, Aloha. "It's such a wonderful thing to come to work with Bradley every day because he has so much passion for not just his character but the whole film -- the whole process," McAdams told ET in April 2015. "He approaches every scene like he wants it to be the best scene filmed ever."
Cooper, meanwhile, returned the compliment, telling ET at the time, "I knew that we would have great chemistry. At least I thought we would based on Wedding Crashers, a movie I'd done with her 10 years ago. I always thought, 'Wow! It's so easy to work with her.' She's so present and it only got stronger after 10 years."
Romance Rumors?: The pair were briefly linked after enjoying a two-hour meal together in Santa Monica, California, in 2013, however, Cooper had just started dating model Suki Waterhouse at the time and nothing came of the tabloid speculation surrounding the actors.
What They've Worked on Together: The Words (2012), Guardians of the Galaxy (2014), Guardians of the Galaxy Vol. 2 (2017), Avengers: Infinity War (2018), Avengers: Endgame (2019)
What They've Said About Each Other: Saldana and Cooper dated, on and off, after sparking a romance on the set of the 2012 drama The Words, in which they played a couple. The heat between them, both on screen and off, was undeniable and drew more attention than the film itself.
Saldana was also effusive with her praise for Cooper, telling The Hollywood Reporter in September 2012, "Bradley is a very dedicated and open professional. It’s really good when you can balance that with an actor as opposed to an actor that just comes prepared and just goes, 'don’t f**k up my light’ and 'this line is my close-up.' We didn’t care where the camera was. It was just like we were both part of this extensive conversation."
Cooper shared similar sentiments about his co-star, who'd go on to be his on-again, off-again girlfriend for several years, telling ET during a junket promoting the film, "Zoe is an incredible actor. The relationship was not as plot-driven once she came on, so we changed a lot of the plot once she came on, because of how committed and what truth she brought."
Romance Rumors?: The pair began dating in late 2011 while filming The Words in Montreal. They kept their relationship -- as well as multiple breakups and romantic reconciliations -- as low-key and out of the public eye as possible, but finally broke things off for good in early 2013. They've remained amicable since, having starred together in multiple Marvel films. While Cooper only provided the voice of Rocket Raccoon, the two have walked many red carpets and sat together for numerous interviews.
What They've Worked on Together: Case 39 (2010)
What They've Said About Each Other: The pair first reportedly sparked a romance together in 2009, three years after meeting on the set of their horror flick, Case 39. While neither of them was willing to directly comment on the swirling romance rumors, they couldn't help themselves when it came to gushing over one another as scene partners while promoting the film's release in late 2010. "He’s a great actor, great actor," Zellweger told ET at the time. "I just got so excited, not believing that I was going to go to work with him."
"I can't say enough about her. I never met her before this, but I just love her. I love coming to work. I love acting with her. I can learn so much from her," Cooper told ET during a press junket for the film, later explaining to Popsugar, "I was super happy to do a movie with Renee Zellweger, who I'm a huge fan of, and to have it work so easily. I feel like it's so easy to work with Renee."
Romance Rumors?: The pair reportedly enjoyed a low-profile romance for several years, although they both declined to ever confirm that they were dating. According to reports, they split in March 2011 as Cooper supposedly became more career-oriented and had less time for the relationship, although he's never commented on their time together or eventual breakup.
What They've Worked on Together: American Sniper (2014), Burnt (2015)
What They've Said About Each Other: The pair met for the first time when Miller auditioned to play Cooper's wife in the Clint Eastwood-directed biopic drama American Sniper, and Cooper said he was in awe of her talent and how she disappeared into the character. "I was always a massive fan of hers and was shocked that she even came in on it," Cooper, who also served as a producer on the film, said at a press conference in New York in December 2014. "When watching the audition, it took 50 seconds before I realized it was Sienna Miller."
Miller returned the compliments, explaining, “For me, it was one of the most creatively enlightening experiences to be around Bradley playing this part. I’ve always been an enormous fan of his… Having seen American Sniper and Elephant Man in the same day, there is just no way that that man is the guy from The Hangover… He has the charisma of a movie star, but he is a character actor of the highest order."
Romance Rumors?: While the pair had undeniable chemistry, and some tabloids tried hard to suggest that they were more than co-stars, both insisted that they were just friends. Cooper and Miller were also in relationships during filming on both their projects, with Cooper dating Waterhouse and Miller dating Tom Sturridge, with whom she welcomed a daughter, Marlowe, in July 2012.
What They've Worked on Together: A Star Is Born (2018)
What They've Said About Each Other: The pair have shared nothing but unbridled love and support for one another since the start of filming on the acclaimed film, and their off-screen friendship and magnetic chemistry was one of the driving forces behind speculation that they were secretly in love, which they've both staunchly denied. However, it's clear they have an unmitigated amount of respect and appreciation for each other.
"He is such an incredible director and, you know, he made me a better actress. I just love him so much and he is such a dear friend of mine and I am just so proud to be here tonight," Gaga said of Cooper at the 32nd American Cinematheque Awards Gala in November 2018, adding that they've remained close even after filming wrapped. "We talk all the time, yeah… And it's exciting and wonderful and we are both so grateful for how the film is being received. You know, that's what's really come out of all of this for me: the reward of a lifetime friendship with someone I deeply respect."
She also famously (and repeatedly) praised Cooper for his faith in her abilities in numerous interviews, sharing, "I've always wanted to be an actress… There can be 100 people in the room and 99 don't believe in you, and you just need one to believe in you. And that was him. So, I'm very lucky to be here."
As for Cooper, who stepped behind the camera as a director for the first time on A Star Is Born, he said working with Gaga made the whole project feel less intimidating, even when it came to singing without any prior experience in that realm. "She made me feel so comfortable from the first day we met," Cooper said during a press conference at the Venice Film Festival in August 2018. "I'd be lying if I said I was nervous...When you see an artist of that caliber treat you as a peer, it's very emboldening. So, the true answer is I didn't [feel afraid]. I felt like I was protected all the time."
Romance Rumors?: Lady Gaga and Bradley Cooper's on-screen chemistry was so strong, it made many people believe there was no way the two weren't completely in love, despite Cooper's relationship, and child, with Shayk and Gaga's own engagement to Christian Carino, which came to an end in February 2019. The split came just days before the 2019 Academy Awards, where Cooper and Gaga, essentially in character, performed one of the most romantically charged duets ever, cuddling up behind a piano on stage while belting out "Shallow" and cranking up the romance rumors to the next level.
Gaga appeared on Jimmy Kimmel Live days after the Oscars and staunchly shut down the speculation and fan theories. "First of all, social media, quite frankly, is the toilet of the internet and what it's done to pop culture is abysmal," Gaga said, rolling her eyes at the rumors. "People saw love and, guess what, that's what we wanted you to see. This is a love song. The movie, A Star Is Born, it's a love story."
"From a performance perspective, it was so important to both of us that we were connected the entire time," Gaga added. "When you're singing love songs, that's how you want people to feel."