 The first step in Castro 's revolutionary plan was an assault on Cuba from Mexico via the Granma , an old , leaky cabin cruiser . They set out for Cuba on November 25 , 1956 . Attacked by Batista 's military soon after landing , many of the 82 men were either killed in the attack or executed upon capture ; only 22 found each other afterwards . During this initial bloody confrontation Guevara laid down his medical supplies and picked up a box of ammunition dropped by a fleeing comrade , proving to be a symbolic moment in Che 's life . 
