Continuity: Miss Marple supposedly searches through the cabin of Lt. Compton, when she finds the suspicious envelope. However, the door sign reads "Capt. Rhumstone". When we take into account that each officer moved into the cabin of the next lower ranking officer, the Captain now lives in the cabin of Commander Breeze-Connington, and that would be the cabin Miss Marple is searching through. Moreover, when moving into the new cabins, all the officers' cabins appear to be located in one single row. Later in the movie, however, they appear to be quite irregularly spread around the deck.
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