With his family away for their annual summer holiday, a publishing executive decides to live a bachelor's life. The beautiful but ditzy blonde from the apartment above catches his eye and they soon start spending time together—maybe a little too much time!
Industrialist François Delambre is called late at night by his sister-in-law, Helene Delambre, who tells him that she has just killed her husband, André. Reluctant at first, she eventually explains to the police that André invented a matter transportation apparatus and, while experimenting on himself, a fly entered the chamber during the matter transference.
An Edinburgh professor and assorted colleagues follow an explorer's trail down an extinct Icelandic volcano to the earth's center.
