cock-and-bull story
US /ˌkɑk.ənˈbʊl ˈstɔː.ri/
UK /ˌkɑk.ənˈbʊl ˈstɔː.ri/

1.
histoire à dormir debout, histoire invraisemblable, conte à dormir debout
a story that is obviously not true, especially one told as an excuse
:
•
Don't give me that cock-and-bull story about why you're late.
Ne me raconte pas cette histoire à dormir debout pour justifier ton retard.
•
His excuse was a complete cock-and-bull story.
Son excuse était une histoire à dormir debout complète.