10 More Best Movie Twists You Genuinely Never Saw Coming
8. Farrell Is Yuri - No Way Out
No Way Out stars Kevin Costner as U.S. Navy officer Tom Farrell, who is being framed for the murder of his lover Susan Atwell (Sean Young).
The actual man responsible, Secretary of Defense David Brice (Gene Hackman), takes part in a plan to pin the killing on Farrell, while also claiming him to be a whispered-about KGB mole codenamed "Yuri."
At film's end, with Farrell and Brice both having sensitive information which could implicate one another, Brice agrees instead to frame his counsel, Scott Pritchard (Will Patton), as both Susan's killer and the mysterious Yuri.
But with the matter seemingly resolved, the final scene reveals that Farrell actually was Yuri all along - an ultra deep-cover spy raised as American from childhood in order to infiltrate the U.S.
Romancing Susan was an intelligence-gathering mission due to her relationship with Brice, though Farrell/Yuri did genuinely fall in love with her, and seemingly quits the spy game at the very end.
This is an outstanding example of a twist that's hidden in plain sight - the bad guys try to frame the hero, and it turns out they unintentionally trip over the truth in the process.