mind-bender
nounUK /ˈmaɪndˌbendə/
US /ˈmaɪndˌbendər/
Something that is very hard to understand or believe.
That puzzle was a real mind-bender.
OTHER MEANINGS
2. A person who uses tricks or persuasion to change how others think.
The salesman was a mind-bender who could sell anything.
3. A story or movie with a surprising plot that makes you think hard.
The film was a mind-bender with a twist ending.
4. A drug that affects the mind.
The old story warned about mind-benders sold in dark alleys.