The stars were pictured on Zac's Twitter page sharing an unusual selfie on set yesterday (07Mar16).
Posing in beachwear and sunglasses, the pair are pictured behind the scenes, with Zac sticking his tongue out at the camera while holding Sacha in in his arms.
In the post he wrote: "Caught this guy creepin (sic) around set today. He showed me a scene from 'The Brothers Grimsby' - I was dying laughing."
Sacha, 44, was appearing in character as Norman 'Nobby' Butcher, an English football hooligan from his new spy action comedy, which is currently on release in the UK and due out in the U.S on 11 March (16).
Zac, 28, is currently filming scenes for the screen adaption of the popular 90s TV series Baywatch, where he plays a former Olympic swimmer turned lifeguard.
The star has recently been spotted showing off his remarkably toned physique doing the shoot, in which producer Dwayne 'The Rock' Johnson leads a team of lifeguards.
Earlier this week (06Marc16) Zac posted a picture of himself and The Rock battling it out in a strongman style competition. They competed to see who could lift a jumbo truck tyre the longest while fans looked on.
It seems High School Musical star Zac is keen to emulate the former wrestler turned action hero's positive attitude. He posted a tribute to the Ballers star on Twitter: "Blood, sweat & respect. The first two you give, the last one you earn." Learned that from @TheRock #Baywatch".
The acting duo have been supporting each other since filming began, after the competition The Rock posted on Instagram (06Mar16): "wait til you see the insane shape my boy Efron got in for our movie. Proud of the hard work he put in."
The Rock was proven right this week after fans were sent into a frenzy (07Mar16) when pictures were released of a make-up artist applying fake tan to Zac's chiseled body on set.
Co-star Kelly Rohrback, 26, plays C.J. Parker, the role that made 90s pin-up Pamela Anderson a global star.
Last week (03Mar16) The Rock revealed that original Baywatch star David Hasselhof will make a small cameo in the new film.
Meanwhile Pamela recently told Harper's Bazaar magazine, "I don't know. I don't like remakes of TV shows and I kind of want to leave it as is and be remembered for that."