You won't believe this...

Meaning

Introducing an unbelievable or surprising story.

Examples

• John: <b>You won't believe this</b>, but I ran into my old college professor at the supermarket!
• Alice: No way! What did you talk about?
• John: It was so unexpected. <b>You won't believe this</b>, but he remembered me from a class project we did fifteen years ago!
• Alice: That's incredible!