Despite a valiant effort, Sing hits more bum notes than high ones and it feels sadly flat. It looks good and the cast all give it their best but it just doesn’t hang together as well as it should. Sometimes all a film needs is heart to help other things fall into place and this lacks that. Sing is fun but it’s not funny enough or engaging enough to fully live up to its promise before the credits roll. There’s a great film in amongst it all, but this isn’t it.