The cast of “Top of the Lake: China Girl” is amazing. Elisabeth Moss, Nicole Kidman, Gwendoline Christie and Alice Englert turn in amazing performances in this second-season sequel.

They’re so good, you can pretty much ignore that writer Jane Campion’s narrative relies heavily on a series of coincidences so unlikely that they seem magical. And not in a good way.

Moss reprises her role as Detective Robin Griffin, whom we met in Season 1 when she dealt with a case in New Zealand that echoed her life. (She was raped as a teenager and gave birth to a child she placed for adoption.) In Season 2, she’s back in Australia dealing with a new murder case and spending time with her biological daughter, Mary (Englert, who is Campion’s real-life daughter).

Kidman stars as Julia, Mary’s adoptive mother. Her marriage to Pyke (Ewen Leslie) has collapsed, and Julia is now involved with a female co-worker.

(Photo Credit: See-Saw Films/SundanceTV) Nicole Kidman as Julia and Alice Englert as Mary in "Top of the Lake: China Girl."

“I consider myself a character actor,” said Kidman, who won a Best Actress Oscar for “The Hours.” “And I really wanted to be in the series. I wanted to work with these incredible women. I wanted to be part of an ensemble and contribute.”

Mary is involved with a much-older man, Puss (David Dencik), who is involved with a local brothel filled with young Asian women. Which is where the murder comes in.

Robin investigates with her new partner, Miranda (Gwendoline Christie, “Game of Thrones”), who, rather comedically, towers over her. But her performance is no joke.

“I was a huge fan of the first series of ‘Top of the Lake,’ ” Christie said. “So I couldn’t believe my luck when I was lucky enough to be in the next series. And I made sure I was prepared because I didn’t want Elisabeth Moss to feel she was dealing with any kind of slouch.”

I won’t give away too much here, but the high drama and performances mask that the narrative becomes increasingly ludicrous. With lesser actors, this might not work. With this group, the plot holes become incidental.

There are big, serious issues here. “Top of the Lake” is about what it means to be a woman and a mother. And the answers are not the typical platitudes we see in television and the movies.

“For me, this season is so much about motherhood,” said Moss. “And Robin’s sort-of main challenge is to figure out how she’s going to be a mother to Mary, essentially somebody who is a stranger.”

The six-episode Season 2 airs in 2-hour blocks on Sunday, Monday and Tuesday at 10 p.m. on SundanceTV. And throughout, Miranda, Mary and Julia “are just constantly pushing [Robin’s] buttons and challenging her, and the most important thing for her is to solve this case. It’s always the most important thing for her.

“And then in typical ‘Top of the Lake’ fashion, of course, the personal always kind of lines up with the political, and she has to kind of figure out both.”

Gwendoline Christie, from left, Elisabeth Moss, Alice Englert and Nicole Kidman participate in the "Top of the Lake: China Girl" panel during the AMC and Sundance TV Television Critics Association Summer Press Tour at the Beverly Hilton on Saturday, July 29, 2017, in Beverly Hills, Calif. (Photo by Richard Shotwell/Invision/AP)