River Phoenix began acting at age 10, and was just 23 when he collapsed and died of a heroin and cocaine overdose outside the Viper Room nightclub in West Hollywood, Calif., on Oct. 31, 1993. His films include "Stand by Me," "Indiana Jones and the Last Crusade" and "My Own Private Idaho."
Amy Winehouse was 27 when she died of alcohol poisoning after years of substance abuse. Ironically, the song she is best known for, "Rehab," is an autobiographical song about Winehouse's refusal to seek treatment.
Andy Gibb, youngest brother to the singing Gibb brothers who formed the BeeGees, died March 10, 1988, just five days after he turned 30. He reportedly died of natural causes brought on by years of substance abuse.
Anna Nicole Smith was 39 when she died on Feb. 8, 2007. Her daughter, Dannielynn, was just five months old. Smith had just lost her son, Daniel, days after her daughter's birth. Her death was ruled a prescription drug overdose.
Martial artist and movie star Bruce Lee died at age 32 on July 20, 1973, of cerebral edema, possibly due to a medication reaction.
Brandon Lee, Bruce Lee's son, was even younger than his famous father when he passed away on March 31, 1993, at age 28. Lee died of a gunshot wound on the set of the movie "The Crow" when a mistake was made with a gun.
Actress Brittany Murphy died on Dec. 20, 2009, at age 32. The primary cause of death was pneumonia, but anemia and intoxication due to use of prescription and over-the-counter medication contributed to her death.
Chris Farley, who starred on "Saturday Night Live" and in a number of movies, died at age 33 of an overdose of cocaine and morphine.
Cory Monteith, who played Finn Hudson on "Glee," died July 13, 2013, at age 31 of a toxic combination of champagne and heroin.
Heath Ledger, best remembered for roles in "Brokeback Mountain" and "The Dark Knight," died at age 28 on Jan. 22, 2008, of prescription drug intoxication. Six months after his death, "The Dark Knight," in which Ledger played Batman villain The Joker, was released to much acclaim. He would posthumously win a best supporting actor Oscar for the role.
James Dean was just 24 when he was killed in a car crash on Sept. 30, 1955. The young actor had already starred in "Giant," "Rebel Without a Cause" and "East of Eden." His early death cemented his legend.
John Belushi was 33 when he died after overdosing on a mixture of cocaine and heroin on March 5, 1982. The "Saturday Night Live" star also made a name for himself with such films as "Animal House" and "The Blues Brothers."
Lisa "Left Eye" Lopes of the R&B group TLC died in a car crash in Honduras on April 25, 2002. She was 30. The singer's final days had been filmed, and the footage was turned into a documentary titled "The Last Days of Left Eye."
Actress and legendary sex symbol Marilyn Monroe was 35 when she died on Aug. 5, 1962, of a barbituate overdose. Her death has led to numerous conspiracy theories, with some calling it a suicide, others believing foul play was involved.
Hip-hop artist Tupac Shakur was shot to death at age 25 on Sept. 13, 1996, as he rode in a car in Las Vegas. His musical rival, the Notorious B.I.G., was also killed in a drive-by shooting just six months later, at age 24.
R&B singer and actress Aaliyah was just 22 when she died in a plane crash on Aug. 25, 2001.