From the liner notes

In one of the best performances of his legendary career, Robert Mitchum plays small-time gunrunner Eddie "Fingers" Coyle in Peter Yates's adaptation of George V. Higgins's acclaimed novel The Friends of Eddie Coyle. World-weary and living hand to mouth, Coyle works on the sidelines of the seedy Boston underworld just to make ends meet. But when he finds himself facing a second stretch of hard time, he's forced to weigh loyalty to his criminal colleagues against snitching to stay free. Directed with a sharp eye for its gritty locales and an open heart for its less-than-heroic characters, this is one of the true treasures of 1970s Hollywood filmmaking--a suspenseful crime drama in stark, unforgiving daylight.

The original theatrical trailer: