A man dressed as Batman walked into a British police station in the middle of the night and told officers "I've caught this one for you" as he handed them a crime suspect.
Police in West Yorkshire, northern England, are baffled after the mystery crime fighter delivered the suspect to a police station in the city of Bradford.
Wearing the full costume of the shadowy comic book hero, including a cape, he then "promptly vanished into the night to fight crime and the fear of crime in Bradford", West Yorkshire Police said.
The force has released a CCTV photograph of the "caped crusader", who is of stocky build, arriving at the police station with his captive.
The force said the 27-year-old crime suspect had been wanted in connection with a string of crimes and has now been charged with handling stolen goods and fraud-related offences. He will appear in court on Friday.
"The person who brought the wanted man into the station was dressed in a full Batman outfit," a police spokesman said. "His identity, however, remains unknown."
Neighbourhood police in the Buttershaw area of Bradford revealed details of the mystery on their Facebook page and the incident was captured on CCTV.
The post sparked a slew of theories on social networking sites about the identity of the crime fighter, including suggestions he may know the arrested man since there was little sign of a struggle.
Bradford's new hero is not the first to pose as a real-life Batman.
In October, a man pleaded not guilty to obstructing US police while dressed as Batman, after he refused to leave them alone while they searched for a driver who had fled the scene of an accident.
Mark Wayne Williams had already been sentenced to six months' probation after police received a report of a man dressed as Batman on the roof of a business in Michigan.