Celebrity Co-Star Affair Rumors We'll Always Wonder About

Some co-star affair rumors never get confirmed, and all we’re left to do is guess.

Of course, we’ve seen many romances arise from an on-screen relationship. Some of our most beloved celebrity couples fell in love on sets. However, plenty never give us the satisfaction of an answer.

Let’s be honest: On-set chemistry can turn into off-set magic, and those lines can get blurred quickly. Sometimes the relationships get confirmed, while other times they become Hollywood lore, like Brad Pitt and Marion Cotillard. Some actors show up on this list more than once — we’re looking at you, Ben Affleck — so this might be a bad habit for some.

Who made our list of rumored couples whose work was so believable on-screen, we think there could have been something off-screen? Take a look and see if you agree.

A version of this article was originally published in March 2021.

Ryan Reynolds & Sandra Bullock

Image Credit: Jason Merritt

After being co-stars in the smash 2009 hit The Proposal, the two allegedly reconnected after their divorces from Scarlett Johannsen and Jesse James, respectively, in 2011, and thus the dating rumors started.

However, in a 2011 interview with Today‘s Al Roker, via People, Bullock said they weren’t dating.

“I think there will be a collective sigh amomgst women across the United States when I say he’s not my lovah,” she replied. “He’s just an amazing friend for 10 years … but I don’t get his loving after dark.”

Glen Powell & Sydney Sweeney

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When early photos emerged of Glen Powell and Sydney Sweeney filming their 2023 rom-com, Anyone But You, it didn’t take long for fans to speculate that the two were having a fling behind the scenes.

Amid the rumors, Powell split from his girlfriend of three years, Gigi Paris. However, Sweeney stayed with her then-fiancé, Jonathan Davino, until their 2025 breakup.

Sweeney denied affair rumors in an August 2023 interview with Variety. “It’s a rom-com,” she said. “That’s what people want! Glen and I don’t really care.”

Paris spoke out about the rumors in June 2025, saying she was “shattered” when Powell didn’t shut down the speculation and felt she was left with no choice but to end things.

Kristin Davis & John Travolta

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Back in early 2024, rumors swirled that Cash Out co-stars Kristin Davis and John Travolta were smitten with one another.

An Insider told Closer Weekly that sparks flew between the stars on set. “People who’ve seen them together say it’s obvious he’s totally smitten,” they said, adding that both of them have been gushing about each other since working on the film.

However, the movie came and went without any dating confirmation.

Charlize Theron & Keanu Reeves

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Back in 2001, Charlize Theron and Keanu Reeves sparked dating rumors after starring together on Sweet November and The Devil’s Advocate, and getting cozy at the 2001 Golden Globes. However, at the time, Theron was beginning her 9-year romance with actor Stuart Townsend.

After Townsend and Theron eventually split, the Daily Mail reported that Reeves joined the actress for an intimate dinner in 2010.

The two have never kept their friendship a secret, but as Reeves continues his longtime romance with girlfriend Alexandra Grant, the ship may have sailed on his romance with Theron.

Zac Efron & Ashley Tisdale

Image Credit: Photo By: Emiley Schweich/Everett Collection

While we know that Zac Efron dated his High School Musical co-star, Vanessa Hudgens, rumors persisted that he and his other co-star, Ashley Tisdale, dated too. How did this start? His 2006 guest appearance as her love interest on The Suite Life of Zack and Cody.

However, Tisdale said she only ever saw him as a brother, saying per People, “It’s because I was friends with him before the movie. He was way younger than me. He was like a brother, too.”

Zac Efron & Lily Collins

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During the press tour for their 2019 movie, Extremely Wicked, Shockingly Evil and Vile, fans were convinced that Zac Efron and Lily Collins were dating, resurfacing old rumours.

A sweet snapshot of the two back in 2012 started the darting rumors, with sources alleging they dated in 2012 and 2013; however, it seems that they’re just great friends.

Aaron Dominguez & Selena Gomez

Image Credit: Gilbert Flores for Variety, Gilbert Flores for Variety.

While Aaron Dominguez and Selena Gomez were filming the first season of Hulu’s Only Murders In The Building, tabloids ran rampant with stories the co-stars were a new item. “She deals with it a lot, I’m sure,”

Dominguez said of his co-star fielding dating rumors during a press junket, per Insider. “When you’re under the spotlight a lot… that’s a pointed topic for her all the time.” Dominguez never outrightly shut down the speculation, so we’re still left wondering if the pair’s on-screen chemistry translated off-screen.

Lady Gaga & Bradley Cooper

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No matter how many times Lady Gaga and Bradley Cooper tell us they are “just friends,” we will never be dissuaded from believing that their romantic — and highly convincing — performance of “Shallow” at the 2019 Oscars was real. That chemistry and their bond in A Star Is Born was so electric, it felt like no one else was in the room — even though millions were watching from around the globe.

Quashing the romance rumors was certainly made more difficult when Cooper split from longtime girlfriend Irina Shayk just a few months after their movie was released.

Gaga understands us, though. She felt it, too — they had each other at “hello.” “The second that I saw him I was like, ‘Have I known you my whole life? It was an instant connection, instant understanding of one another,” she told Vogue in 2018. Maybe they were lovers in another life — just not this one.

Liam Hemsworth & Jennifer Lawrence

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After fans heard Liam Hemsworth ex-wife Miley Cyrus’ song “Flowers,” which insinuated he’d cheated and was dropped on Jennifer Lawrence’s birthday, many assumed the Hunger Games co-stars had an affair.

Lawrence has admitted to secretly kissing Hemsworth but shut down affair rumors during a June interview on Watch What Happens Live.

“Not true, total rumor,” the No Hard Feelings star said of the allegations. “I mean, we all know me and Liam, like, kissed one time. It was years after they’d broke up.”

Will Smith & Margot Robbie

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Now that Jada Pinkett Smith’s “entanglement” with singer August Alsina has been revealed, it’s time to revisit Will Smith and Margot Robbie’s clearly visible on-screen chemistry in 2015’s Focus.

There were rumors that there might have been something more than just a friendship in the tabloids after the two were seen canoodling together during a cast party, per Page Six. And we know that Will alluded to the fact that he hasn’t been a complete angel in his marriage during that frank Red Table Talk with his wife.

We are putting this pairing as a strong maybe, right?

Blake Lively & Ben Affleck

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While Blake Lively and Ben Affleck were filming The Town in 2009 in Boston, the paparazzi always seemed to catch them touching while the cameras weren’t rolling. He also gushed about her on Anderson Live and it just felt a little extra. “She is fabulous as you can see, she’s a gorgeous young woman,” he said. “She was in The Town with me and she was fabulous.”

It doesn’t help that Affleck wasn’t on his best behavior during his marriage to Jennifer Garner, so this keeps the possibility open: Might there have been more to this working relationship than meets the eye?

Armie Hammer & Lily James

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The rumors around Rebecca co-stars Armie Hammer and Lily James surfaced around the same time as James and Dominic West’s carefree jaunt around Rome. The press wasn’t cutting the young actress a break, but she warned everyone during an interview with Grazie that what we see on social media and in the tabloids are “a complete minefield and very rarely what things appear to be.”

Michelle Pfeiffer & John Malkovich

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Go back and watch 1988’s Dangerous Liasions, and tell me the heat between Michelle Pfeiffer and John Malkovich didn’t melt the screen. You had to throw water on everyone around you because the flames were everywhere.

So did this on-screen scorcher carry into real life? Hmm, it’s been reported that Malkovich cheated on his then-wife Glenne Headley with Pfeiffer, but then years later he basically denied that anything ever happened with them — or that they even worked together.

“It’s hard to believe Michelle Pfeiffer ever said hello to me — not that she’s not memorable, God knows. But I sort of blacked it out,” he told Esquire two decades later. “What I’m trying to say is, when I think of the other person, I don’t think of me as involved with them. They’re uncorrupted by me. As if they were never troubled by my existence.”

We call that rewriting history, my friend.

Jennifer Lawrence & Chris Pratt

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Anna Faris did not love the rumors coming from the set of Passengers in 2016 alluding to the possibility that her then-husband Chris Pratt might be having an affair with co-star Jennifer Lawrence. Faris revealed in her memoir, Unqualified, that the gossip and constant media stories made her “feel insecure,” per US Weekly.

Lawrence took a direct approach to squashing the rumors, but it took her almost two years to address the issue. “I never had an affair with Chris Pratt on Passengers,” she told KISS FM. “That’s a good one. I mean they got a divorce like two years later and everybody was like, ‘Jennifer Lawrence!’ And I was like, ‘What the… what I’m in Montreal two years later.’”

Marion Cotillard & Brad Pitt

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We totally forgot about this one, but there was always a cloud of suspicion around Allied co-stars Brad Pitt and Marion Cotillard. The reason why we forgot is that these rumors dropped right around the time Angelina Jolie filed for divorce.

A Page Six source claimed in 2016 that Pitt was “in the throes of some insane midlife crisis.” Yet insiders on Cotillard’s side swore that she was solid with longtime boyfriend, French actor and director Guillaume Canet. “They are still very much together. They have been a couple since 2007 and have one child, but have never married.”

Lots of on-set photos showed Pitt and Cotillard looking cozy together, but maybe it was just great acting?

Amanda Bynes & Channing Tatum

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The level of cuteness between Amanda Bynes and Channing Tatum, seen in a 2006 interview for Fuse’s Daily Download, is off the charts. They were promoting She’s the Man and they were flirtatious with a capital “F.” (Watch her call him “Chan” — we love it!) There’s no denying that there was at least a crush going on.

Nothing has ever been confirmed or denied by these two, but Tatum has been supportive of Bynes after years of struggles with her mental health.

“I love her,” he told Entertainment Tonight in 2018. “I’m so happy she’s killing it again and just back on the right. She’s so talented and so special. She’s been doing it… I mean, I think it’s so impossible when you start at such a young age to keep perspective. It’s tough.”

Tom Cruise & Hayley Atwell

For years now, people were convinced that there was something going on between Mission Impossible: Dead Reckoning Part One co-stars Tom Cruise and Hayley Atwell. However, in a 2023 interview with the Independent, Atwell confided that she sees Cruise as an “uncle,” and she added that the “weird” rumors were never true!

Paris Hilton & Chad Michael Murray

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You are going to need a scorecard for this entire story. Back in 2006, Paris Hilton — yes, she acts — and Chad Michael Murray starred in House of Wax together. Hilton was dating Backstreet Boy Nick Carter and Murray was married to Sophia Bush. There were rumors that the two co-stars enjoyed each other’s company beyond the pages of the script.

No one confirmed nor denied any of the tabloid stories until Carter opened his big mouth to Ryan Seacrest on KIIS FM in Los Angeles. He claims that not only did Hilton and Murray cheat, he says his act of revenge on his then-girlfriend was to hook up with Ashlee Simpson.

Does that make this alleged situation a love pentagon?

Emily Ratajkowski & Ben Affleck

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Emily Ratajkowski seduced Ben Affleck on-screen in Gone Girl, but it’s hard to tell if they practiced those acting scenes off-screen. There was a lot of smoke when it came to the rumors, but there never seemed to be any fire. Ratajkowski often talked about the big age difference between the two of them and it made us feel like she really wasn’t interested in an older man.

“The whole experience was a little surreal, I have to be honest,” she told The Today Show about working with him. “Obviously, Ben Affleck is one of those – you know his face. I grew up with that face! Not sure he would like that.”

Emma Watson & Tom Felton

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Yup, we’re talking about Harry Potter now. For years during and after the franchise, fans wanted to see Emma Watson and Tom Felton together. Watson even revealed she was in love with him when she was younger, telling fans during the Harry Potter 20th anniversary special.

She claims she fell for him on Harry Potter and the Sorcerer’s Stone, saying, per EOnline, “I used to come in every day and look for his number on the call sheet, it was No. 7, and if his name was on the call sheet, it was an extra exciting day,” she said during the reunion. “He was three years above me and so for him he was like, ‘You’re like my little sister.’”

But they have, and always will be friends!

Matthew McConaughey & Kate Hudson

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When you saw How to Lose a Guy in 10 Days, you couldn’t help but wonder if the spark between Matthew McConaughey and Kate Hudson was real. Even today, people wonder, despite both of them claiming time and time again that they’re just close friends.

David Duchovny & Gillian Anderson

People shipped David Duchovny and Gillian Anderson both on and off screen, but nothing ever came from it. In fact, they reflected that they butt heads a lot on the show, but as of the 2020s, they’re working on mending a friendship, according to New York Post.

Jennifer Lawrence & Bradley Cooper

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Not only have Jennifer Lawrence and Bradley Cooper co-starred in multiple films together, but they’ve been at the center of dating rumors for almost a decade, starting back in 2012 with Silver Linings Playbook. Multiple interviewers asked Cooper about their relationship and if it turned romantic, to which he said “No” every time, per EOnline.

Sandra Bullock & Keanu Reeves

Since starring in Speed together in 1994, rumors have persisted about Sandra Bullock and Keanu Reeves. For decades, people have been convinced that they’ve had an off-screen romance. However, Bullock shut that down when speaking to Esquire, saying, “Nope. But who knows? Keanu’s a guy who, I feel like, is friends with every woman he’s ever dated. I don’t think there’s anyone who has something horrible to say about him. So maybe we could have survived. I don’t know.”

Brad Pitt & Julia Roberts

Ever since the early 2000s, pals Brad Pitt and Julia Roberts have been at the center of dating rumors. It originally started back in 2001 with films like Ocean’s Eleven and The Mexican. The rumors persisted throughout, and even as recent as 2019, when tabloids claimed Roberts was having an affair with Pitt, per IBT. (Hint: she wasn’t, but fans have been obsessed for literal decades.)

Reese Witherspoon & Mark Wahlberg

After being linked together as an on-screen matchup in Fear, Mark Wahlberg and Reese Witherspoon were the center of dating rumors throughout the mid-1990s. However, neither have ever confirmed or denied the rumors.

Celebrity Co-Star Affair Rumors We’ll Always Wonder About