When they met the first time in a grimy gym off Times Square, the boxer and the wordsmith were the most unlikely of friends. They were teenagers with bright futures from opposite corners of New York City.

More than a decade later, one of them is dead and the other is about to stand trial for his murder.

James Butler, the boxer, came from the tough, unforgiving New York. He lived in a housing project in Harlem with his mother, who preferred night life to child rearing, and he spent time in foster care and in jail. His father was never around.

Sam Kellerman, the wordsmith, came from the gilded, privileged New York. He lived in a posh prewar apartment building on Fifth Avenue. His father, Henry Kellerman, is a prominent psychoanalyst and author; his mother, Linda, is an artist.

Quick-witted and outgoing, Kellerman was an overachiever. He went to the competitive Stuyvesant High School and graduated from Columbia University.