In his short career, though, he became something of a poster boy for the grunge generation, thanks to his understated but intensely charismatic performances in movies like Gus Van Sant’s My Own Private Idaho.
His tragic demise on the pavement outside LA’s Viper Rooms nightclub only helped cement his status as a screen icon.
But he could certainly act a bit too, as he showed from his first major roles as a teenager.
Here are some moments worth remembering him by....
Arguably the most emotional moment in a real heartstring-tugger of a movie, and Phoenix is at the centre of it.
His character Chris Chambers has already been labelled as a wrong ‘un by association due to his family of bruisers (“kid brother to Eyeball Chambers”), and has recently been accused of stealing milk money from his school.
During the four lads’ journey to find the body of a missing local boy, Chris confesses to the film’s narrator Gordy that he did steal the money, but then returned it to the teacher because he felt bad.
He then saw the teacher in school wearing a new skirt, and realised she had kept and spent the money herself, knowing no-one would believe that Chris had returned it.
The sense of betrayal by the supposedly trustworthy adult world is brutally resonant, and his tears feel painfully real.
He later admitted, “I identified so much with the role of Chris Chambers that if I hadn't had my family to go back to after the shoot, I'd have probably had to see a psychiatrist.”
The confession scene in Running on Empty (1988)
In love with his piano teacher’s daughter (Martha Plimpton) but unable to commit to a relationship because his parents are fugitives still wanted for crimes as anti-Vietnam activists in the early ‘70s, his long-hidden life story comes pouring out.
The pent-up emotion that has smouldered through the movie is released, as he tells his then real-life girlfriend: “I don’t know what I’m doing… and I love you.”
The fact he looked witheringly gorgeous throughout didn’t stop us believing him, and helped establish him as a bona fide teen heartthrob.
Opening scenes of Indiana Jones and The Last Crusade (1989)
The third movie in the franchise begins with Phoenix (a boyish-looking 18), playing the 13-year-old Indy spotting the theft of an archaeological treasure while on a boy scout horse-riding trip.
The resulting action sequence sees our young hero displaying the same slapstick comedy touches as well as the grumpy charm of Harrison Ford’s Jones, to the point where he looked every inch a chip off the old block.
His resemblance to a young Ford gave him a head start, but Phoenix then practised by mimicking Ford on set for laughs and set about trying to copy his mannerisms to further get under Indy’s skin.
The opening scene from My Own Private Idaho (1991)
“I know where I am from looking at the road,” says Phoenix’s little-boy-lost protagonist as he stands in the Midwest of nowhere.
With his beanie hat-wearing, bumfluff stubble and name-tagged thrift store shirt, as well as that pretty face, he was an instant poster boy for the grunge generation.
The rambling monologues to himself and berating of the rabbit (“We’re stuck here together you shit”) draw us in from the first scene, before the brilliantly acted narcoleptic episode and dream sequence where he’s back in the arms of Mom. A star is born.
The Campfire scene from My Own Private Idaho (1991)
“I’d like to talk with you,” stammers Phoenix’s narcoleptic gay hustler Mike to his straight best friend and fellow male prostitute Scott. “I mean I’d like to really talk with you.”
Long silence. “I don’t feel like I can be close to you.”
It’s a beautifully played portrayal of unrequited love and unspoken desires, full of so-pregnant-they’re-expecting-triplets pauses and agonising tension, as well as an undercurrent of humour and innocent romance.
Given the fact that the pair were said to have struggled to play the scene straight due to winding each other up over playing a gay scene, they’re pretty damn convincing.
And it helped make both actors superstars – even if one didn’t have long to enjoy it.
The restaurant scene in Dogfight (1991)
In this relatively little-known but well-received indie flick, River plays cocky Marine Eddie Birdlace who has met Rose (Lili Taylor) as the result of a macho competition among his buddies to pull an unattractive girl.
Naturally he falls for the bookish young waitress, but when she finds out the reason why he first approached her, she wants nothing more to do with him.
He promises to make amends with dinner in a posh restaurant, but they are turned away for being too scruffy. After which, he takes her to a nearby clothing store and buys a dinner jacket, with the price tag still hanging off the shoulder.
He loudly struts in with her and loudly humiliates the waiter as he takes his seat. This annoys Rose, who also complains about his swearing. Then the real belly-laugh: to show Birdlace her point, she gives her order to the waiter while swearing copiously (“The dirty bastard salad with a sh**load of Roquefort dressing”). Birdlace’s face is a picture as he is left speechless.
All of which makes for another cute snapshot of River Phoenix’s strongest suit talent: playing troubled, vulnerable young characters that you can’t help falling in love with.
