Salvatore "Sal" Mineo, Jr. (January 10, 1939 – February 12, 1976) 

Sal Mineo was was a film and theatre actor, best remembered for his role as
John “Plato” Crawford opposite James Dean in the 1955 drama film Rebel
Without a Cause. He was nominated twice; for the Academy Award for Best
Supporting Actor; once for his  performance in Rebel Without a Cause, and
also for his portrayal of Dov Landau in Exodus (1960).  

 
Sal Mineo (L) with James Dean from Rebel without a Cause