Pulpy thriller “You” starring Penn Badgley as murderer Joe Goldberg became a sensation when it landed on Netflix last year — attracting 40 million viewers, according to the streaming network.

Season 1 — which originally aired on Lifetime but struggled to find an audience on the cable network — followed the seemingly charming New York bookseller Joe as he wooed, stalked, and ultimately murdered his girlfriend Beck (Elizabeth Lail). Co-created by super-producer Greg Berlanti and Sera Gamble (“The Magicians”), “You” is both a psychological thriller and a satire, toying with genre conventions in rom-coms and stalker stories.

Netflix picked it up exclusively for Season 2, premiering Dec. 26.

“I think we all were surprised [the show was such a hit]” says co-star Ambyr Childers, 31, who plays Joe’s ex, Candace Stone. “It did OK on Lifetime but unfortunately they didn’t renew it, and Sera and Berlanti took it to Netflix. I think it’s a great example [among the] many shows that have moved platforms and really made it successful for everybody.”

In Season 1, Candace appeared in scattered flashbacks. She was presumed to have met the same fate as Beck — fatally slain by Joe, spelling out a pattern for how he treats his loves. But in a season-ending twist, she was revealed to be alive, and Season 2 picks up with Joe fleeing from New York to LA, fearing that Candace will expose him to the world. After all, to everyone who doesn’t know about his penchant for murdering, Joe seems like a mild-mannered sensitive guy.

“Candace embraces this vengeance as a radical form of therapy,” says Childers. “She wants revenge, she wants payback. She plays this vigilante character that I really love in the second season. It’s super-fun, like a cat and mouse game.”

As Joe spends Season 2 backed into a corner and fearing Candace, he’s also still up to his old tricks — targeting a new girl named Love (Victoria Pedretti, “The Haunting of Hill House”).

But as captivating as “You” can be, there are many soapy shows, and many thrillers out there. So what made so many people tune into this series when it premiered on Netflix? Childers thinks there are two reasons: it’s based on a popular book of the same name, and it often invokes social media in its storyline.

“I think people are fascinated with serial killers and the whole mindset of people like Joe, and social media obviously is a big driving force of this younger generation,” she says. “It’s also based on a really fantastic book — it’s a really solid show that a lot of different generations can tap into.”

Since “You” is so popular, there are, naturally, differing opinions about Joe’s behavior. Some fans even embrace it, which Childers finds fascinating.

“It was funny, I was reading some of the comments on Instagram this morning of people’s reactions to even the teasers [for the show],” she says.

For instance, one user commented “I don’t know why Joe gets such a bad rep. He’s a man that would do anything for the woman he loves. He’s alright in my book.”

“There are some pretty sick f–king people out there!” says Childers. “It’s just mind-blowing. I think it’s important for people to know that Joe’s actions and behavior are not okay. It’s really fascinating to see how this all has transpired into some women just being so in love with this idea of who Joe is.

“I’m so fascinated with how our brains work and how fiction works and how we get so obsessed with these types of television programs.”

Ref;nypost.com