The Island at the Top of the World (1974)

A Victorian gentleman hopes to find his long-lost son, who vanished whilst searching for a mysterious Viking community in a volcanic valley somewhere in uncharted Arctic regions. The gentleman puts together an expedition team to go on the search, but when they reach their destination they must escape from some Viking descendants who will kill to keep their existence a secret.
Robert Stevenson
Donald Sinden, David Hartman, Jacques Marin, Mako, David Gwillim, Agneta Eckemyr, Sverre Anker Ousdal, Gunnar Öhlund, Lasse Kolstad, Erik Silju, Rolf Søder, Torsten Wahlund, Niels Hinrichsen, Denny Miller, Brendan Dillon, Ian Abercrombie
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