song and dance vs cock-and-bull story

song and dance and cock-and-bull story both are nouns.

Word	Noun	Adjective	Verb	Adverb
song and dance	Yes	No	No	No
cock-and-bull story	Yes	No	No	No

As nouns, song and dance and cock-and-bull story are synonyms defined as:

song and dance and cock-and-bull story: an interesting but highly implausible story; often told as an excuse

Other synonyms of song and dance include fairy story, fairy tale, fairytale.

song and dance (noun)	cock-and-bull story (noun)
theatrical performance combining singing and dancing	an interesting but highly implausible story; often told as an excuse
an interesting but highly implausible story; often told as an excuse