The twist here is that the country girl, on her way to the big city, first has to endure a 15-year detour when she falls off a ferry and washes up alone on a deserted island.

She has a heavy country dialect, but that falls away when she opens her mouth to sing and a powerful voice drifts out capable of captivating anyone within earshot.

Her captivated audience includes her classmate Jeong Gi-ho (Moon Woo-jin) and K-pop icon Yoon Ran-joo (Kim Hyo-jin).

Mok-ha is a Ran-joo überfan who takes part in a singing competition put on by the star. She needs to shoot a video to enter and the only person around her with a video camera is Gi-ho.

The serious and bespectacled Gi-ho at first appears to be the opposite of Mok-ha. All he seems to care about is making a buck, but he and Mok-ha share more in common than they at first realise. Gi-ho also has an abusive father, a local police officer. The reason he needs cash is to run away.

Ran-joo is blown away by Mok-ha’s entry, but by the time the latter learns she has won the contest and is invited to Seoul, things have got so bad at home that the near-catatonic Mok-ha has abandoned her dreams.

A concerned Gi-ho implores her to come to him the next time she fears for her life. That soon happens, and when a barefoot and soaking Mok-ha taps on his window in the middle of a stormy night, he packs his things and decides to escort her to Seoul himself to meet her idol.

They board a ferry to the mainland, but as she escapes from her father, who has tracked her down, she falls off into the ship’s wake. Presumed dead, she washes up on a small, deserted island where she subsists on potatoes and seafood for the next decade and a half.

For his part, a despairing Gi-ho soon makes his own getaway from Cheongsam Island, never to be seen again. He does so after smashing the fish tanks in Mok-ha’s father’s seafood restaurant and releasing the animals into the sea.

His outburst is bittersweet, since it calls to mind the time he told Mok-ha she could wind up dead like one of the neglected, upturned fish in the tank.

Fast forward to the present, when Mok-ha (Park), now 31 and still living on the deserted island, comes face to face with a drone. The drone belongs to reporter Kang Woo-hak (Cha Hak-yeon), who is part of a volunteer clean-up crew, along with his brother, TV producer Kang Bo-geol (Chae Jong-hyeop), who have visited the island.

Mok-ha returns to an unfamiliar society and tries to track down Gi-ho and Ran-joo, who in the meantime has also become a washed up diva.

Castaway Diva’s lively opening episodes pull you in with their earnest sentimentality and clever plotting.

By the close of episode one we’re thoroughly drawn by the teenage Mok-ha’s plight and by the rousing finale of the next, when she steps into the shadows of a stage, lip-synching for a drunk Ran-joo, all the elements combine to heart-rending effect.

If anything can be described as a disappointment so far in the splendid opening episodes, it is that we are given precious little time with Mok-ha on her island.

We bear witness to her first day there and her last, by which time she’s erected a charming jungle abode. Hopefully the show will take some time to revisit this lengthy period of her life later on.

The show is dropping hints that Woo-hak, who has a murky background, may actually be Gi-ho, but let’s hope the show sidesteps such a contrivance-masquerading-as-fate in favour of something more original.

Castaway Diva is streaming on Netflix.