What is a summary of the story After Twenty Years by O Henry?

"After Twenty Years" by O. Henry is a short story about two friends, Jimmy Wells and Bob, who made a pact to meet again in exactly twenty years at a specific spot in New York City. Jimmy, now a successful police officer, is stationed at that spot to fulfill their pact.

Bob arrives, nervous and uncertain, his appearance changed by a life of crime. He doesn't recognize Jimmy at first, but Jimmy recognizes him instantly. A grueling internal struggle ensues: Jimmy's duty to arrest Bob, his loyalty to his friend, and his own sense of justice clash.

In a poignant twist, Jimmy, with a heavy heart, decides to let Bob go, sending him a note warning him to leave the city. The story ends with a sense of bittersweet loss and a haunting reminder of the power of friendship and the consequences of choices.