'Love Story' Stars Ali McGraw and Ryan O'Neal Reunite 45 Years Later for 'Love Letters'

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Love Story co-stars Ryan O'Neal and Ali McGraw opened up about reuniting for the national tour of Broadway's Love Letters, nearly 45 years after the release of their classic romance flick. Spoiler: Their chemistry as is strong as ever.

"You know there's a feeling that great love stories don't end up together," O'Neal told ET. "That's the heartbreak of love."

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The format for A.R. Gurney's 1988 play is simple -- actors read their "love letters" while seated at a desk. The little rehearsal and memorization required has attracted a rotating cast of big stars, including Mia Farrow and Brian Dennehy.

While Love Letters covers romance, it also explores loss and how love transforms over time. In real life, McGraw, 76, and O'Neal, 74, have survived both intense love and loss of their own. McGraw's ex-husband, Steve McQueen, died of a heart attack in 1980 while battling cancer, and O'Neal lost his love, Farrah Fawcett, after a long battle of her own with cancer. Those experiences could make their performances richer than they would've been four decades ago.

"It's the reality of life, and as we get older and older, it's more a part of the story," McGraw explained.

O'Neal and McGraw skyrocketed to fame in 1970 when Love Story opened to wide critical acclaim, and went on to win five Golden Globes and picked up the Oscar for Best Original Score. The intimate tale was a hit that took everyone by surprise.

"Nobody ever expected it to become, I don't think, the phenomenon that it became," McGraw said. "Certainly I was stunned."

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Love Story was only McGraw's third movie, and the first time the co-stars met, they had to kiss as a part of their audition. O'Neal told ET he had never been kissed like that before.

"My lips were all bruised from the kiss," O'Neal recalled. "It's true! I swear to God!"

O'Neal and McGraw's tour launches in Los Angeles on Oct. 13.