Holy hero party! Batman's in town
The actor who plays the caped crusader in the upcoming Batman v Superman Dawn Of Justice film has surprised and delighted a group of children by dropping in on their superhero party.
The Detroit Free Press said the family welcomed the visitors.
Affleck is in Detroit for the filming of the Warner Bros movie, set to be released in May 2016.
The indoor Detroit Kid City features a pint-sized market, cabin, car factory, schoolhouse and other buildings.
Detroit Kid City worker Garrett Dixon says Affleck "was very interested in getting a Detroit Kid City out in LA".