Two Federal Air Marshal Service, Jack Hammond and alcoholic Bill Marks, separately board a British Aqualantic Airlines Boeing 767 from New York City to London. Marks sits next to Jen Summers, who has switched seats so she can be by the window. After takeoff, Marks receives a text message on his secure phone stating that someone will die every 20 minutes unless $150 million is transferred to a specified bank account. Marks breaks protocol and consults Hammond, who dismisses the threat. Marks, however, has Summers and flight attendant Nancy monitor the security cameras while texting the mysterious person to try to identify him.