Star Trek: 10 Things You Didn't Know About Dr Leonard 'Bones' McCoy
7. He Nearly Stood Up To Khan
In 2020, a deleted scene from the Original Series episode Space Seed went viral on YouTube, which showed McCoy standing up to Khan after he overpowered the crew and demanded control of the Enterprise.
In the scene, McCoy approached Khan with phasers pointed at him from all angles, and told him, 'I never thought I'd say this to a patient, but you owe me something! In case you've forgotten, I saved your life!' In his frustration, he grabbed a hold of Khan's arm and was shot to the ground by one of the other Augments. Khan explained to Spock that McCoy was simply stunned, and that he tried to 'avoid bloodshed if possible'.
It's not really known why this scene was cut, but it might have been to make Khan seem more threatening. After all, we know that in the final cut of the episode, Khan actually tried to kill Kirk in a decompression chamber, which made him seem much more insane, while keeping it non-violent enough for the television standards at the time.
Still, this deleted scene is a rare showcase of McCoy's bravery under pressure, even if it's not technically canon.