Someone is killing people related to a South American expedition. The means of murder are poison darts with rubber spiders attached to them. A writer and some police detectives investigate.
| Actor | Role |
|---|---|
 O.W. FischerReporter Wellby | Reporter Wellby |
 Karin DorClarisse | Clarisse |
 Doris KirchnerHelen Osbourne | Helen Osbourne |
 Werner PetersWilliam Osbourne | William Osbourne |
 Eddi ArentFish | Fish |
 Klaus KinskiBoyd | Boyd |
 Claude FarellMrs. Dyke | Mrs. Dyke |
 Gabriel LlopartSelwood | Selwood |
 Fernando SanchoSlim | Slim |
 José María CaffarelCartwright | Cartwright |
 Antonio CasasBronsfield | Bronsfield |
| TTomás BlancoNot listed | Not listed |
 Félix DafauceNot listed | Not listed |
 Cris HuertaNot listed | Not listed |
 Ángel MenéndezNot listed | Not listed |
 George RigaudNot listed | Not listed |