This film is based on an popular series of crime novels written by Folke Mellvig. Mellvig was also one of the screenwriters to this film, and this film was also the first of the so called Hillman detective films.Just like in Sherlock Holmes, The Thin Man, the Hillman couple would solve crimes together. This one has a generic storyline but have an eerie, darker feel, which sometimes borders on Gothic horror.The story is simple about a girl that disappears and Hillman and his wife, together with a stuttering, bumbling assistant Freddy tries to solve the case. But it proves to be very hard....Two main actors Annalisa Ericson(Kajsa Hillman)and Karl-Arne Holmsten(John Hillman) had great chemistry on screen. The same kind of banter, and razorsharp wit that William Powell, Myrna Loy had in The Thin Man (1934).I don't think this film and its sequels could have been that successful without them. And with supporting comedic relief from Nils Hallberg(Freddy Sjöström) they carry this film with excellence.Director Arne Mattsson did a great job creating suspense and also adding a very creepy, Gothic horror style to this film. Using a great musical score, and a talented cinematographer Sven Nykvist(who would work with Bergman, Woody Allen among others) he makes a top notch thriller from the 50's.The problem with film is the very generic storyline, and the problem of clichés that are prevalent in this film. Sometimes it feels like watching any episode of the Scooby Doo series.But as always it is better then most Swedish crimethrillers made today, this film creates far better atmosphere then Strandvaskaren (2004). Future Swedish genre filmmakers should watch this film for that reason only.Even though Mattsson did a better thriller later on in his career, Yngsjömordet (1966), this one isn't bad. Anyone interested in Swedish crimethrillers should check this one out.