This coming Tuesday, October 30, will mark 25 years since River Phoenix died outside the Viper Room, on Sunset Boulevard. Now, for the first time, his then-girlfriend, the actress Samantha Mathis, has shared her memory of that tragic night, in an interview with The Guardian.

Phoenix—older brother of Joaquin, star of Stand By Me, Oscar nominee before he could even legally drink—was just 23 when he, Mathis, and his younger siblings stopped by the Viper Room for what Mathis thought was just a drop-off. “When we arrived, he said to me: ‘Oh, there are some people playing music tonight in the club who want me to play with them—that’s okay, right?’” recalls Mathis. “I knew something was wrong that night, something I didn’t understand. I didn’t see anyone doing drugs, but he was high in a way that made me feel uncomfortable—I was in way over my head.”

Mathis, who now lives in New York and reportedly started to cry during the phone interview, was born the same year as Phoenix; she could tell when someone was using drugs, but of course, she couldn't control it. She recalls that she was in the Viper Room bathroom when Phoenix injected the drugs that caused his overdose. “I knew he was high that night, but the heroin that killed him didn’t happen until he was in the Viper Room. I have my suspicions about what was going on, but I didn’t see anything,” she said. Then Phoenix got into "a scuffle with another man" and the group was pushed out of the club by a bouncer. On the sidewalk, Phoenix began to convulse.

As Mathis shouted at the man Phoenix had been fighting and yelled for help, Joaquin called 9-1-1. By the time the paramedics arrived, the young star was dead.

Mathis hasn't spoken at length about that night in the quarter-century since "except to [her] therapist," she says, but a recent viewing of The Thing Called Love, Phoenix's final film and the one in which he costarred with Mathis, inspired her to reflect on her youthful love, and what he might have been up to now if he'd survived. “River said to me in that last year: ‘I just have to make one more movie to put away enough money so my youngest sister can go to college,’” Mathis said. “I don’t know if that was true, but I remember him saying that.” But she thinks that he would have continued being an artist, and an activist—Phoenix was deeply committed to environmental and animal rights causes. “I think if River was still here, I think he’d be acting, directing, saving the environment, just living and hanging out. Oh gosh, wouldn’t that be nice?”

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