Noun
likely story (plural likely stories)
Used to suggest that someone's story or excuse is a lie.
He told me he couldn't come because his budgie had fallen ill. A likely story!
A likely story - and probably true. Groucho Marx
I shall often discuss mathematical discoveries... I shall try to make up a likely story how the discovery could have happened. I shall try to emphasize the motives underlying the discovery, the plausible inferences that led to it... everything that deserves imitation. George Pólya