When fighting organized crime, you never know where the clues will lead. For instance, the investigator in Underground Mafia City Escape was working on a case involving a particularly dangerous gang, and the investigation led him to the criminals' lair. It turned out they were hiding in underground tunnels. Realizing he couldn't delay, the hero decided to catch the bandits by surprise, but he found no one. He had fallen into a trap, and the door slammed shut behind him. If he doesn't find a way out, the investigator will be trapped in this grim place forever.