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Joaquin Phoenix‘s older brother River was an Oscar-nominated rising star in Hollywood before his sudden death at age 23 from a drug-induced heart attack outside L.A.’s Viper Room nightclub in 1993.  The last film he made, Dark Blood, was never completed, but it will be now with help from Joaquin.

The original Dark Blood footage had been kept in storage but is now re-edited. George Sluizer, the film’s director, plans to ask River’s brother, to voice parts of the movie, saying, “The voices of both brothers are very much alike.”  In Dark Blood, River takes on the role of a hermit living in the desert on a nuclear testing site as he waits for the end of the world.

Eyeworks, a company based in Holland is helping Sluizer finish up the film and cope with any potential legal problems surrounding a planned 2012 release, says The Hollywood Reporter .

Prior to his death, River Phoenix was very much in-demand as an actor, taking starring roles in Stand by Me, My Own Private Idaho and Sneakers.  He was nominated for an Academy Award as best supporting actor for his role in the 1988 movie Running on Empty.