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Movies like Schlafwagen Paris-München (1965)

The Paris-Munich overnight express becomes the scene of an unusual crime. Private detective Frank Winter is assigned a "case" of unknown proportions! He has 20 minutes to reach the train in Strasbourg as ordered and make contact with a stranger in the S 98 sleeping car. The task is to protect the French scientist Prof. Charles Leduc, an expert in the field of cybernetics...