If anyone asks, our cover story is that we were at the library studying all afternoon.
The speaker is setting up a shared, believable excuse with a friend to avoid getting in trouble.
Noun phrase: cover story
Vibe: Deception and self-protection
A made-up story or believable excuse used to hide the real reason behind what you are doing.
We need a cover story in case anyone asks why we left work early.
You picture two friends whispering in a hallway, quickly agreeing on the exact same lie so they don't get caught sneaking out.
Real-life examples
We used a fake dinner reservation as a cover story to get her to the surprise party.
Shows how a cover story can be used for harmless, fun secrets rather than malicious lies.
Synonyms
Contrast & nuance
A 'cover story' is a detailed, pre-planned lie designed to protect a secret. An 'alibi' specifically proves you were in a different location so you can't be blamed. An 'excuse' is usually a quick reason made up on the spot to avoid trouble.