In the photo, Zac looks world's away from the famous face we know and love with the 33-year-old rocking a scraggly beard and appearing worse for wear with a black eye as he holds up some kind of device, appearing to look for signal.
Gold is the star's first film project since arriving in Australia earlier this year when the pandemic struck.
The movie is a thriller about "greed and the lengths people will go to secure themselves a fortune" according to Stan.
Zac plays one of two drifters travelling through the outback. They stumble across the biggest gold nugget ever found and dream of their imminent wealth.
They come up with a plan to protect and excavate their bounty with one man leaving to secure the right equipment for the job and the other staying in the harsh desert climate to protect the gold, while also coming to the realisation he may have been abandoned.
Zac jokingly shared the snap to Instagram with the caption: "No signal out here in the desert…"
One follower joked in return: "This is a common problem here in Australia."
Many others commented on the fact the star hasn't posted any photos since September with one user writing: "Please don't disappear again!"
"I'll come rescue you Zac," another fan wrote.
"Room for one more?" someone else asked.
Up until recently, Zac had been spending his time in Byron Bay after escaping the pandemic in the US.
It was believed he and his Aussie girlfriend Vanessa Valladares split up recently, however, this has yet to be confirmed as the former waitress was spotted in Adelaide with the star recently.
After coupling up with Zac in July, the 25-year-old has reportedly since ditched her day job and shacked up with her A-lister beau at his Belongil Beach home.
According to TMZ, Zac plans on permanently relocating to Australia as he feels safer here than in the US where the coronavirus pandemic shows no signs of slowing down.
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