For season three of “Crazy Ex-Girlfriend,” Aline Brosh McKenna wanted to “get inside of some of the more extreme aspects” of Rebecca Bunch’s (Rachel Bloom) personality to better understand her psychology. McKenna co-created the CW series with Bloom about a mentally-unbalanced lawyer who leaves a job at a successful New York firm to pursue the love of her life, Josh Chan (Vincent Rodriguez III), in West Covina, CA. The creators “felt like we owed a diagnosis to really try and figure out what’s going on with Rebecca, because obviously ‘crazy’ doesn’t mean anything medically.” Watch our exclusive video interview with McKenna above.

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Season three begins with Rebecca out for blood after Josh leaves her at the altar. “When you think of the title of the show, revenge is what you think of,” McKenna explains. “So that was one of the things that we felt we always owed, was to look at the ‘crazy’ aspect of being a crazy ex-girlfriend.” However, “revenge is a poison meant for someone else that you take yourself. It doesn’t actually do anything but make her feel worse, and it starts a spiral” that raises the question, “what really is wrong with this woman?”

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Rebecca eventually attempts suicide, leading her to seek therapy. That’s when she’s diagnosed with borderline personality disorder, a long-term pattern of abnormal moods and behaviors. But having a diagnosis doesn’t simply “make the problems go away,” McKenna says. “So she still has so much to deal with.” Indeed, Rebecca’s actions start to catch up with her later in the season. “All these bills start to come due, and she doesn’t yet have completely the coping skills to” deal with them. The season ends with Rebecca realizing “that she needs to be responsible for all the crappy things we’ve seen her do since she got to West Covina,” leading to a shocking conclusion.

McKenna received BAFTA, WGA, and USC Scripter nominations for her screenplay for “The Devil Wears Prada” (2006). She and Bloom won the Gotham Award for Breakthrough Series for the first season of “Crazy Ex-Girlfriend” in 2016. Additionally, she has penned scripts for such films as “27 Dresses” (2008), “Morning Glory” (2010), “We Bought a Zoo” (2011), and the upcoming Cruella de Vil origin story “Cruella.” She also co-created the new series “Arranged,” due to premiere in 2019.

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