December is the season for serious Oscar movies, but if you’re looking for something light and diverting, animals singing their hearts out is just the ticket.

After the fluffy-looking “The Secret Life of Pets” (also from Illumination Entertainment) took an unexpectedly dark turn, I was relieved that “Sing” delivers exactly what you expect from the trailers: A group of underdogs finding their own voices while competing in a singing contest.

Will Rosita (Reese Witherspoon), the underappreciated mom of 25 piglets, get a chance to shine? Will shy elephant teen Meena (Tory Kelly) find the courage to get on stage? Will gorilla Johnny (Taron Egorton)’s gruff gangster dad ever realize his son’s gift? Will rocker porcupine Ash (Scarlett Johansson) write a song that brings down the house?

There’s no real surprises in any of those story arcs, but the movie still reaches its happy ending in an enjoyable way, aided by a soundtrack of hits from Taylor Swift to The Beatles.

In a storyline very much like 2011’s “The Muppets,” the contest’s koala emcee, Buster Moon (Matthew McConaughey) has his own dreams of saving the bankrupt theater his late father helped him buy. And cynical, Sinatra-esque mouse Mike (Seth MacFarlane) just wants glory and a taste of the good life.

“Sing” might not break any new ground, but it will likely make you laugh and send you out with a smile.

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