Young Dorothy Wynant approaches amateur sleuth Nick Charles when her inventor father appears to be a major suspect in a murder case. In fact, Dorothy is so worried about her father's guilt that she tries to convince Nick that she did it. Nick's wife Nora wants him on the case so that she can experience some of the excitement herself. However, Nick is reluctant to get involved until he sees that police Lt. Guild is coming to the wrong conclusions. Nick decides that the best way to clear up the case is to invite all the suspects to dinner with Lt. Guild and see what happens...—Gary Jackson