The siblings introduced a challenge during the first episode, sharing that the queens needed to make runway outfits that "celebrate the natural beauty of our homelands".
It wouldn't be an Irwin appearance without some kind of reptile also making an appearance, with the siblings joined by Jenny the Burmese python who lay across their shoulders.
"We are massive fans of Drag Race, aren't we Bindi?" Robert began, with Bindi adding, "We sure are, Robert. Art Simone's impersonation of me last season was truly... inspirational."
Bindi then added with a laugh, "Just kidding!", with the queens loving her sass.
The siblings explained the challenge and Robert was tasked with signing off with one of RuPaul's signature catchphrases: "Good luck... and don't f**k it up!"
However, the 18-year-old wasn't quite able to get the words out, saying, "Good luck, and don't... Nah, I can't say it! I'll leave that to you, Ru!"
The queens were stunned as they watched, thinking Robert was about to swear but laughed as he held himself back.
Fans loved the moment, with one user writing, "The Irwins calling into the Werkroom on Day 1 to celebrate Down Under's natural beauty, ugh it's such a moment."
"I didn’t realise how much I wanted to hear Robert Irwin say the F word until #DragRaceDownUnder," another joked.
"I wanted to see Robert Irwin say 'f**k'," a third wrote.
"My only disappointment from this episode is that Robert Irwin didn’t say 'f**k'. Maybe next time..." someone else added.
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