Dr. Petrov: The reason for having two missile keys is so that no one man may...
Captain Ramius: May what?
Dr. Petrov: Arm the missiles Captain. Perhaps I should keep the key.
Captain Ramius: Thank you. That'll be all, Doctor.

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After announcing Putin as dead, Dr. Petrov takes exception to Ramius taking the Political officer's Missile key and keeping it.

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