Posting a promo shot of herself with her co-star Charles, Rebecca penned: "These two are nearly here."
"Meet Louis Oakley and Daisy Monroe - a disbarred London lawyer and a Sydney Socialite with nothing in common other than the failing vineyard they’re about to inherit in the South Island of NZ," she explained, before adding, "What could possibly go wrong?!"
The actress, who is also an executive producer on the series, then shared her hopes for how the characters will be received by fans: "I hope you’ll fall in love with them as much as I have."
The series comes to life after Rebecca's character Daisy heads to New Zealand for a vacation at her recently deceased stepfather’s winery, which she intends to sell.
It's there she crosses paths with the vineyard's co-owner, a grumpy UK-born lawyer, Louis Oakley, who also travels to New Zealand to escape a spiralling series of unfortunate events in his life.
Despite neither having done a hard days' work in their lives and both despising each other, Daisy and Louis must somehow make the vineyard successful so they can sell up.
When speaking about the series, Rebecca reiterated what she hopes audiences will love, while also sharing what she loves about it.
"This series made me smile and cry when I read it, and while I filmed it. I'm working with the most extraordinary crew and the cast," she said.
"Charlie and I have created a couple that I haven't seen since like the ‘40s and that's what I love about this because it's like an old Hollywood romance.
"It's good fun. It's lighthearted. It's heartfelt. It's not grubby. It's set in a beautiful place. It's kind of like a time gone by."
Under the Vines is available to stream on Acorn TV from December 6, and you can sign up here.