Fallout 4, it was Paladin Danse IIRC.

I like the Fallout series, but man, the Institute was such a badly written villain. They make synths, they treat them like robots, okay, that’s understandable. They had the tech to rebuild the country, but nooo, they chose to kidnap people and replace them with synth doppelgängers because fuck know why. They were inexplicably obsessed with duplicating people.

Oh, and you don’t have to kill Danse, you can convince him to defect.