Based on S.E. Hinton's YA novel of the same name and directed by Francis Ford Coppola, the 1983 crime drama was Rob's debut, pairing him opposite other future screen icons like Matt Dillon, Diane Lane, Patrick Swayze, C. Thomas Howell, and Tom Cruise.
His experience with the latter was the most intense, as the 59-year-old entered a discussion about competing with his co-star and their cycle of "one-upping" each other.
"[Tom was] ambitious, never met anybody more ambitious, and I am ambitious," Rob said. "There was a lot of one-upping going on…Tom's part of Steve Randle was not a huge part, but Tom being Tom, he was ambitious."
Host Bruce asked about the infamous rumor that the future Oscar-nominee had removed a cap from his front tooth for the part, and Rob confirmed that it was indeed true.
The 9-1-1 actor also added: "Francis also thought that we should all be gymnasts, for some reason. So we all had to learn to do backflips.
"Tom took it so seriously. If you see The Outsiders, the movie is playing and the movie just stops dead and Tom does a backflip off of a car."
With its cast full of future Hollywood heavyweights, the film emerged as a success after release, becoming a critical darling and a minor box office hit.
It has since become a classic, and is considered the first of the so-called Brat Pack films of the 1980s, an umbrella term which featured the same few young stars frequently appearing in teen coming-of-age movies of the time.
Rob was one of those considered part of the unofficial cinematic club, alongside Outsiders co-star Emilio Estevez, plus Anthony Michael Hall, Andrew McCarthy, Demi Moore, and Molly Ringwald.
While the term itself has received mixed reception from its stars, having deemed it a means to "pigeonhole" them, the movies of that era have largely become classics of the genre, including Sixteen Candles, The Breakfast Club, St. Elmo's Fire, and Pretty in Pink, to name a few.
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