Wiktionary
merry dance
n. (context idiomatic English) A useless waste of time resulting from a deception.
Usage examples of "merry dance".
Indeed, in one corner some of the young Tooks and Brandybucks, supposing Uncle Bilbo to have finished (since he had plainly said all that was necessary), now got up an impromptu orchestra, and began a merry dance-tune.
Instantly she joined hands with two of the Maenads, who whirled her round in a merry dance and helped her take off some of the unnecessary and uncomfortable clothes that she was wearing.
Our quarry led us a merry dance, keeping close enough to be seen but not to be apprehended.