"It’s our responsibility to go as deep as we can and explore all the directions that might even be suggested in the script," River Phoenix once told Interview Magazine, regarding the acting process. "Just so we have all the bases covered. Our research was extracurricular; it wasn’t necessarily needed."

When he won the Oscar for Joker back in 2020, Joaquin Phoenix took time to thank his late brother and fellow actor. Phoenix died at the young age of 23, but by that time, he had already starred in quite a few awards-caliber films. See below for our top 5 list.

5 The Mosquito Coast (1986)

Actor Justin Theroux is currently starring in an Apple TV+ series adaptation of the acclaimed novel by his uncle, Paul Theroux. But first, there was a film adaptation in 1986 starring Harrison Ford, Helen Mirren and Phoenix. The Mosquito Coast tells the story of a family that leaves the U.S. and tries to find a happier and simpler life in the jungles of Central America. However, their jungle paradise quickly turns into a dystopia as their stubborn father's behavior becomes increasingly erratic and aggressive. Phoenix is reliably superb as the young son in distress. We can't wait to see what thrilling surprises season 2 of the streaming series brings.

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4 Indiana Jones and the Last Crusade (1989)

Here's another acclaimed Ford-Phoenix collaboration. What an honor to be able to play a younger version of the heroic Indy. Phoenix appears in a fun cameo role in the third Indiana Jones installment, which also stars Sean Connery as Indy's dad. The father-son relationship between Henry Jones, Sr. and Indiana Jones was a pure joy to watch. After being absent from Indiana Jones and the Temple of Doom, the Nazis returned as the film's main villains. In Indiana Jones and the Last Crusade, they searched for the Holy Grail, believing that it would grant them eternal life. Once again, Indiana Jones was back to fighting Nazis. The film successfully shifted to a lighter tone after Temple of Doom, and it was tons of fun seeing Phoenix own the young Indy role. And we're simply counting the days until the franchise's fifth film hits the masses.

3 My Own Private Idaho (1991)

In one of his more difficult roles, Keanu Reeves plays the character of Scott Favor, a sex worker and friend of Phoenix's Mikey Waters. The heartbreaking, gritty indie film My Own Private Idaho deals with heavy themes of poverty, mental illness, and closeted queerness. Mikey confesses his love for Scott, who then rebuffs him as he falls in love with a woman. At the end of the celebrated Gus Van Sant film, the boys are separated by consequence, with Scott falling into money and opportunity and Mikey perhaps left worse-off than before. It's one of Phoenix's best roles — and the same goes for Reeves, the John Wick actor who's been churning out action flicks ever since. It's therefore refreshing to see him in this more dramatic turn.

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2 Running on Empty (1988)

Here's yet another acclaimed drama starring Phoenix from the celebrated '80s decade. Running on Empty follows the Popes, a family that hasn't been able to use their real identity for years. In the late '60s, the parents set a weapons lab afire in an effort to hinder the government's Vietnam War campaign. Ever since then, the Popes have been on the run with the authorities never far behind. Now, their older son (Phoenix) wants a life of his own, although he is aware that would mean that his parents would either get caught or he will never see them again. Phoenix was rightfully nominated for the Best Supporting Sctor Oscar that year, further proving that he had gifted acting chops from quite a young age.

1 Stand By Me (1986)

And speaking of acclaimed performances at a young age — Stand by Me is perhaps the best of the best when it comes to Phoenix's filmography. The heartwarming/heartbreaking drama is based on King's novella The Body, in which a group of four young boys discover the body of a missing boy when they're out on a hike. The name of the film comes from the 1961 hit song by Ben E. King. The beloved film adaptation features young stars Phoenix, Wil Wheaton, Corey Feldman, and Jerry O'Connell in monumental roles for their ages. Stand by Me is a unique body of work for King, but it's one of his most poignant adaptations that still resonates with audiences today. Phoenix's campfire scene where he becomes emotional when addressing the theft rumors surrounding his troubled character is reason enough to check out Stand By Me.