Requiem for a Heavyweight traces the downward spiral of Mountain McClintock, a heavyweight boxer past his prime. A former contender for heavyweight champion of the world, he never quite ascended that peak. But he gamely fought on until now, when the advancing years have taken their toll on his speed, stamina and physical condition. He still hopes for the big bout that will restore him to prominence. What he doesn't know is that his manager, Maish Resnick, will cruelly betray him. A glimmer of hope arrives for Mountain in the person of Grace, a social worker assigned to find Mountain transitional employment, but who also falls for him. But Maish and a wrestling promoter have their own plans for Mountain... plans that may destroy whatever dignity Mountain has left.