Aline Brosh McKenna discusses the Emmy-winning series' return, which includes new guest star Scott Michael Foster.

Since its premiere, “Crazy Ex-Girlfriend” has had to balance multiple ambitious intentions: to create musical television with original songs, to sell a relative unknown as its star and to stand out from the rest of the genre programming on The CW. Not only did the Emmy-winning series succeed on all fronts, but it also put an intriguing twist on the romantic comedy genre: interpreting the familiar tropes through the lens of mental health.

While our titular protagonist Rebecca Bunch (Rachel Bloom) may not be literally insane, her behavior does raise questions of her mental stability. After all, she threw away a mid-six figure salaried job in New York for life in the far more humble West Covina, California, just because her childhood ex Josh Chan (Victor Rodriguez III) lives there. But after a season of increasingly erratic behavior, somehow — through magic perhaps? — she finally ended up with Josh in last year’s finale. Season 2 picks up with Rebecca having had her heart’s desire fulfilled, which has only served to reinforce her delusions of romantic destiny.

READ MORE: ‘Crazy Ex-Girlfriend’ Emmys: Crafting Those Wacky Songs

“That’s exactly it,” co-creator and showrunner Aline Brosh McKenna told IndieWire in an interview. “She sort of was not admitting to herself why she was even in town. She wasn’t even really admitting to herself that she was in love with Josh. So now she has that absolute conviction that they love each other and they’re meant to be together. It’s kind of the next phase of romantic obsession, where you go from having really a crush to having a certainty. That really heightens the level of her obsession.”

Read on for McKenna’s insight into what other characters and elements will be reaching another level this season:

Scott Everett White/The CW

Rebecca’s Men

Brainy bartender Greg Serrano (Santino Fontana) had actually pined over Rebecca for a while before she finally gave into their obvious chemistry. But his self-destructive behavior in the finale pushed her away, straight into the arms of a newly single Josh.

“When will he get his act together?” McKenna mused. “ I think the trajectory of his life would’ve been completely different had it not been for Rebecca. Season 1 really set the stage for all the reverberations, and in Season 2 Greg is also dealing with all the things that he’s learned about himself, partly due to Rebecca’s insanity kind of stirring the pot.”

Scott Everett White/The CW

Meanwhile, Josh is now saddled with the reality that is Rebecca’s love turned on full blast. “Towards the end of last season he was sort of falling for her more than she was for him because she was preoccupied with Greg. And in that last scene she feels like she woke up and realized that the Josh thing was meant to be and that the Greg thing was, ‘God bless the broken road that led me to Josh.’ Then the question is how long is that going to last? And what is Josh going to do when confronted with the romantic certainty of this very intense young woman?”

As Rebecca’s idealized man, Josh hadn’t had the most revealing scenes character-wise, but Season 2 aims to rectify that oversight now that they’re together.

McKenna said, “We really do start to understand how Josh has gotten to the place that he is in his life, where’s he’s a little under-utilized as a human being. He was a very popular guy in high school and a popular guy in his hometown. And he’s a bit adrift and in search of his own identity. I think if she had never shown up in town, he would’ve just continued coasting along happily and be on the track that he was on and married Valencia and had children. So whatever happens between him and Rebecca, she’s certainly shaken up his idea of himself and what he should expect from the world. That continues to reverberate in the second season.”

Pal Paula Proctor

On a more positive note, Rebecca’s presence in West Covina has brightened the life of her coworker Paula (Donna Lynne Champlin), whose stagnant marriage was revitalized after having been involved in Rebecca’s pursuit of Josh.

“Rachel and I have always said that main love story of the show is Rebecca and Paula,” McKenna said. “They have a lot of ups and downs this year and we really explore their relationship more and get at the underpinnings of their relationship.”

Scott Everett White/The CW

The Sleeper Power Couple

Rebecca’s boss Darryl Whitefeather went through a sexual awakening after his divorce, when he realized he was bisexual and almost stumbled into a relationship with Josh’s friend White Josh (David Hull). The surprising pairing earned an even more surprising following of shippers.

“We always knew that Daryl was a bisexual character but we didn’t realize we were going to pair him with White Josh until we kind of mixed the cast around and sort of saw people interacting,” McKenna said. “Darryl is a very sweet, kind of trusting, almost naive person. And White Josh in his way is smart and wise, an overly practical person. We just found a rapport there that we really loved, and those two actors are wonderful together.

READ MORE: ‘Crazy Ex-Girlfriend’ Showrunner Brings Logic to the Series

“[This season] we continue to see a lot about their relationship,” she added, “but we kind of want to explore the realities of what they might be going through in a relationship with each other and not just have them be sort of adorable window dressing. What I love about them is that they’re different generations, different backgrounds, different work life, different histories — really different phases in their life. What does it mean to be in a relationship with someone who you have not that much in common on the surface?”

Rob Latour/REX/Shutterstock

Scott Michael Foster

Fans of Scott Michael Foster, who knew him from “Greek,” “Chasing Life” or his other TV appearances, may have forgotten that he sings and plays guitar in an indie band. Fortunately, “Crazy Ex-Girlfriend” rediscovered this talent when he auditioned for a guest role.

“He’s so amazingly talented. We are so, so lucky that he came in for us. Thrilled,” McKenna said. “Do people know that he’s a great singer? He’s done theater in the past and he was in a band. I don’t know that he’s sung so much on television but he’s an amazing singer and I think people are going to be really excited to see what he can do. He blew us away, quite frankly.”

READ MORE: ‘Crazy Ex-Girlfriend’ Season 2 Teaser Trailer Looks Extra Wild (and Sexy)

Foster will play yet another love interest for Rebecca. “He is also from the San Gabriel Valley but he’s from Pasadena, which doesn’t identify itself as being from the San Gabriel Valley,” she added. “So he’s from a different world from the rest of the people in West Covina, and he’s from a more kind of upscale environment. He’s involved in the legal stories of the show.”

Musical Numbers

By now, everyone has seen the sneak peek of the show’s “Lemonade” spoof called “Love Kernels.” But in case you haven’t or just want to enjoy it again, here you go:

“We have another big tap number coming up,” promised McKenna. “We have pop, we have R&B, we have a contemporary dance that we’re just going to have to do. Our aim is to never repeat genres, so we’re doing all different genres this year.”

Unfortunately, there won’t be an animated number, like Bloom’s “Historically Accurate Disney Princess Song” that had caught McKenna’s interest in the performer in the first place. “We’d love to do more animation, but it’s so very expensive and slow. We did just a little bit of it last year,” McKenna explained. “But we do have a princess song, and it’s Paula’s. It’s not animated, but it is a princess song.”

Greg Gayne/The CW

West Covina and the Boba Stand

Instead of the usual coffee shop or neighborhood bar, Rebecca and her friends often meet up at the local boba tea stand. The sweet Asian drink/snack with chewy little tapioca balls is representative of how the SoCal city has assimilated the culture of its diverse residents.

McKenna said, “When [Rachel and I] wrote the show, we were going regularly to West Covina. She and I both like to write from a place of specificity. We wanted to do a specific small town and we wanted to do what do suburbs look like now. And what they look like now is they’re more racially diverse and integrated than cities. All our background and all our casting reflect the population of West Covina, which is about 50 percent Hispanic and a quarter Asian. So at this point it’s second-nature to everyone on the show that we reflect the diversity of the city.

“The boba is Becca and Josh’s little Eden, their little getaway,” she added. “It’s the place where they see each other in a sort of idyllic setting for them. That’s why it looks the way it does. As the show evolves this year, the hangout evolves too. So we have a new hangout that joins us also. It’s going to alternate with boba. It’s another beloved SoCal snack.”

“Crazy Ex-Girlfriend” returns for its second season on Friday, Oct. 21 at 9 p.m. on The CW. Season 1 is currently available to stream on Netflix.

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