 After donning a spare uniform, Dimpfelmoser, Kasperl and Seppel attempt to lure Hotzenplotz back into the firehouse with the help of a false treasure map.Hotzenplotz discovers the ruse and locks Kasperl, Seppel and Dimpfelmoser into the firehouse, but they free themselves by using the fire truck to break through the walls.In the meantime, Hotzenplotz returns to Grandmother's house, kidnaps her and brings her to his hideout, where she is forced to be his housekeeper.