"What the heck, USA?" he wrote. "We didn't even know if you'd understand what they were saying!"
But he then followed up by admitting, "Actually, I assume there's some rewatching to try and understand what they're saying."
And a US fan admitted, "Half the time I actually don't know what's being said during Wellington P [sic] but I'm so into the show that I forget to turn the closed-captions on."
"I had a US friend message me to ask what 'boil the jug' means," a Kiwi viewer wrote on Twitter.
"He thought it was something to do with doing laundry."
Another American viewer wrote in response, "We enjoyed Flight of the Conchords, so of course we understand what's being said.
"It's a very good program, we're happy in the US to finally join in on the fun watching Wellington Paranormal."
The news may come as a surprise, but What We Do in the Shadows gained a cult following in the States when it was released. And it's clearly given American fans a taste for deadpan Kiwi humour.
Now officers O'Leary (Karen O'Leary) and Minogue (Mike Minogue), the brains and brawn behind Wellington's fictionalised paranormal unit, have become household names in the US.
The What We Do in the Shadows spinoff also inspired another TV show with the same name, produced by Clement and Taika Waititi for HBO. It also streams on Neon in New Zealand.
Three seasons of the show are currently available to watch on TVNZ OnDemand in New Zealand.
