Underrated concept: Conflicting mind control commands.
Character gets hypnotized by two different villains, completely unrelated to one another, and the hypnotic commands are exact opposites of one another.
Oh, and they hear two conflicting trigger phrases at the same time.
There's so much good stuff here.
-Mind control isn't meant to conflict, so character goes insane. Just starts acting crazy and erratic, because they don't know which command to obey. They basically become a glitchy NPC, walking into walls, pouring a drink into empty air instead of a cup, etc.
-Character is fighting between their true self, and two strange compulsions in their head. Literal battle in the character's brain as they wonder what the heck is happening
-They frantically talk about everything they "must" do, and it's nonsense:
"Don't you SEE!? I have to kill everyone on my team so I can take them alive without killing them! It's the only way I can kill them all!"
-Alternatively, it makes the character act drunk, too loopy to follow either order, and just blissed out
-Or, character becomes extremely paranoid and hostile, unable to tell friends from enemies. Everyone must be out to get them. That's why they're so confused. It has to be!
-Character passes out when they hear both trigger phrases at the same time
-Or they just freeze, standing wide-eyed, unable to think at all. Just full-on Windows error screen.
-Character starts obeying both commands at the same time in a way that makes no sense
-Their team notices how weird they're acting