The actor noted that his hookup with the G.I. Jane star occurred while they were members of the Brat Pack and starring in St. Elmo's Fire — but before Moore, now 61, became engaged to Emilio Estevez in 1985. The couple ended their engagement the following year and Moore went on to marry Bruce Willis in 1987.

Rob Lowe talked about the couples that formed and broke apart while filming "St. Elmo's Fire," including his crush on Demi Moore.

Decades later, Lowe says he still keeps in touch with Moore, and they are in a group chat exploring a possible St. Elmo’s Fire sequel. According to the star, the entire case is on board. “It’s going a little more slowly than I would have liked, but that’s a good thing because we’re trying to find the right writer and the right story," he shared.

Emilio Estevez, Andrew McCarthy, Demi Moore, Judd Nelson, Ally Sheedy, Andie MacDowell, and Mare Winningham co-starred in the 1985 film.

Lowe and Moore were famously part of the “Brat Pack,” a group of young ’80s Hollywood It-stars, including Emilio Estevez, Anthony Michael Hall, Andrew McCarthy, Ally Sheedy, Judd Nelson, Molly Ringwald.

Rob Lowe and Demi Moore’s romance in 1986’s About Last Night wasn’t just an on-screen fling. During an Oct. 22 appearance on Kelly Ripa’s Let’s Talk Off Camera podcast, the 9-1-1: Lone Star actor, 60,

Lowe and Moore, who were both famously considered part of the “ Brat Pack ” of young Hollywood stars in the ’80s, also costarred in 1985’s St. Elmo’s Fire. During their conversation about the film, Ripa, 54, once again brought up Moore, 61.

Rob Lowe shared the details of secretly hooking up with his co-star Demi Moore in the 80s. Scroll down to read the conversation between the actor and Kelly Ripa, as Lowe shared details.

Rob Lowe shared that he and Demi Moore had a "brief" romance during their days in the Brat Pack and insisted that he and his St. Elmo's Fire costar have remained friends since it ended.

Rob Lowe recently opened up about a short-lived romance with fellow Brat Pack member Demi Moore, revealing that the two had a brief fling

Rob Lowe says he's 'very much in contact' with Demi Moore about the development of a 'St. Elmo's Fire' sequel, and has an idea for his character arc: 'Is Billy sober?'