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Zac Efron Wishes 'Goofball' Zendaya A Happy Birthday With A Silly Pic

Just one 'Greatest Showman' star sending love to another

Considering how Zac Efron spent a ton of time this summer palling around with The Rock for various Baywatch press engagements and ball-busting buffoonery, "the biggest goofball I know" is a pretty big compliment coming from him — and that's exactly what he gave Zendaya.

Efron and Zendaya have been learning the circus ropes on the set of The Greatest Showman, the romantic musical that tells the story of P.T. Barnum and the origin of his legendary circus. We caught a glimpse of Zendaya's pink, cotton candy-esque hair in the first trailer for the film — in which she plays a trapeze artist, and he plays a playwright — and Efron gave us a look of their on-set shenanigans with a quick pic to wish his co-star a happy 21st birthday on September 1.

Even when she's scrunching her face up and rocking some fluffy slippers in costume she still looks like a badass. (Same goes for Zefron and that Danny Zuko-level 'do, not to mention those suspenders.)

The Greatest Showman hits theaters on December 25, so here's hoping we see more sneak peeks of the hilarious duo in action in the coming months.