Grete Hansen is looking for work at "Morgenbladet". Here she meets the womanizer Vilmer, who wants Grete to meet him on her first night out on the town, and Bob, a young man who plays private detective. When Bob reads that there are a number of counterfeit 100 kroner notes in circulation, Bob and Grete decide to catch the thief. First they break into the home of a policeman whom they suspect of being a counterfeiter. Later they play servants at the home of another suspect. Then Grete discovers something suspicious about Vilmer - she follows him to a spooky house.
