"We had no intention of holding back in any way. So the fact that people felt very moved by it is very moving for us."
Moss plays June/Offred, a "handmaid" in the service of a commander's family who is ritually raped as part of a forced surrogacy program. In the show, the US has been taken over by the Republic of Gilead, a theocratic autocracy in which women are enslaved in prescribed roles.
The show has been universally praised for its writing, cinematic visuals and performances, especially Moss, who is up for a Best Actress Drama Emmy, her eighth nomination.
The Handmaid's Tale is now prepping for its second season. Moss says they are location scouting and "deep in the planning", with the writers room having reconvened in April.
A second season wasn't a guarantee and the first season finished at the same point as the book it was adapted from, Margaret Atwood's seminal 1985 novel.
Moss points out the first season already featured significant differences from the source material so the challenge for the next instalment isn't as daunting as some would think.
"There are characters that die or disappear in the book and we keep them alive and give them different stories," she says. "We're not as afraid of [departing from the book] as some would think because we feel like we've already done it in a way that fans of the book really loved. And Margaret was happy with that.
"It's more of the same for us and anything we get to invent now is exciting. We get to create a world that Margaret Atwood would've wanted to continue doing."
Moss's other high-profile TV project this year, Top of the Lake: China Girl, is currently screening on Sky's UKTV with the actor reprising the role she originated in 2013.
There are thematic similarities between the two series, with motherhood and surrogacy threaded throughout the stories.
"As a woman in her 30s, those are very relevant subjects for me so I'm not surprised there is that parallel. It's a very present idea and it's kind of interesting for me to get to explore a similar theme but in a different way.
"Maybe in my 40s, I'll be addressing a different area and in my 50s another."