A dragnet is a method of catching criminals by casting a wide net across an area, searching thoroughly and systematically until the suspects are found.

When police set up a dragnet, they might search an entire neighborhood, question many people, or set up checkpoints on all the roads leading out of an area. After a bank robbery, investigators might cast a dragnet across the city, checking hotels, bus stations, and airports to find the thieves before they can escape.

The word suggests a comprehensive, organized search that doesn't miss anything. If your family is searching for lost car keys, you might joke about establishing a dragnet operation, checking every coat pocket, cushion, and drawer until the keys turn up.

Dragnet also became famous as the name of a 1950s police television show that followed Los Angeles detectives as they methodically solved crimes. The show's realistic, step-by-step investigation style made it one of television's earliest and most famous police dramas.