A washed-up wedding singer bonds with a fading boy-band star, but when the pop star turns one of his songs into a comeback hit, he risks everything to reclaim the credit he believes he deserves.

We’ve all seen "The Greatest Showman," right? The circus at the heart of the tale would announce itself with posters, noise and fanfare. It’s a clear message of: Come one, come all — there’s a show in ...