Changes from the Book
The misunderstood gorilla, Ranko, crushes a rock that Tintin throws at him, something that did not happen in the book. Another change was that the counterfeiting ring based in the castle only consisted of Puschov, Dr. J.W. Müller and Ivan, whereas in the book, it was made of an additional two anonymous members, and Ivan was only portrayed as Puschov's nameless assistant.
- Colin O'Meara - Tintin, Fred the Fireman
- Susan Roman - Snowy
- John Stocker - Detective Thompson
- Dan Hennessey - Detective Thomson