When Your Number's Up, a short story

A jealous mobster approaches a hitman—regarded as the best in his line of work—to eliminate a rival for his lady love's affections. The project violates several of the hitman's self-imposed rules, but when he declines, the mobster showers him with an irresistible increase in his usual fee. The project has a time constraint and this constraint limits his ability to plan adequately, causing him to botch the job. As a consequence, someone affected by the hit comes after him, intent on assassinating the assassin. After two close calls, his nemesis catches up with the hitman in Costa Rica, where the odds are no better than fifty-fifty he will survive.