Looking for a movie. A typical misleading creation with an unexpected ending. A newlywed couple travels to a small island, but there are rumors that there is a murderer on the island.

If you guessed it right, the author is looking for "The Deadly Companion"

Plot summary (from Baidu Encyclopedia): It tells the story of Frank, an American tourist who went to Europe alone to heal his emotional wounds, but failed. On the train, he meets Elise, a sexy woman with a mysterious background. Just as Frank is intoxicated in their world, the crisis is gradually approaching. He has been tracked and monitored since Paris, and when he arrived in Venice, he was hunted down by all parties... With Elise When Frank's true identity is revealed, he realizes that he has been involved in a carefully planned and dangerous game!

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