Since the moment Brittany Snow showed up as Anna on “Crazy Ex-Girlfriend” a few weeks ago, we couldn’t wait for her to break out into song. But the “Pitch Perfect” star didn’t get a solo musical number in her premiere episode, and then Anna didn’t appear onscreen last week at all. Finally, on Friday night (Dec. 9), Snow absolutely slayed the series’ fall finale with such a hilariously disturbing song — hats off to witty writers Rachel Bloom, Aline Brosh McKenna and Michael Hitchcock! — that she had us cringing, and laughing to the point of tears.

RELATED: The ‘Crazy Ex’ girl squad was a hard pass, but Paula & Rebecca are forever

In the episode, “Who’s the Cool Girl Josh is Dating?” Rebecca (Rachel Bloom) and Valencia (Gabrielle Ruiz) fall down a dark rabbit hole of Internet stalking after discovering a photo of Josh (Vincent Rodriguez III) posing with a hot blonde on Instagram. The fact that they both came across the same picture, and it wasn’t even a photo that Josh posted, should give you pause. And the depths they go to learn everything about Anna, and the emotions they go through as they discover information no normal stranger would ever usually want to know, is an embarrassing delight to watch.

crazy ex gif Brittany Snow slays Crazy Exs fall finale with the most disturbingly funny song

The lengths a person who’s not so emotionally stable will go to get the 411 on a person they’re suspicious of is immeasurable. Hell hath no fury like a jealous ex, and still raw from their break-up with Josh (Vincent Rodriguez III), there is nary a limit to Rebecca and Valencia’s new mission.

Who's The Cool Girl Josh Is Dating?

It’s amazing to think where Rebecca and Valencia would be in life if they took the dedication, creative skill and time they spent researching Josh’s new girlfriend and put it towards — oh, we don’t know — literally anything else, but as they Google-stalk, Anna beckons to them with song, from the computer screen…

brittany snow tease gif Brittany Snow slays Crazy Exs fall finale with the most disturbingly funny song

With a sexy come hither voice, she taunts the girls to keep searching even deeper. Create a fake account with the name of one of her high school friend’s names, so they can friend her on Instagram and get access to her private account.  As the song continues, the directives taken to get more details on Anna get more and more disturbing, and it will embarrassingly deeply resonate with most viewers.

rebecca guilty gif Brittany Snow slays Crazy Exs fall finale with the most disturbingly funny song

Internet stalking is an art. A talent about which no one brags publicly, but something every person, at one point or another in life, has been guilty of doing. This is one of the reasons “Delete Internet Search History,” is an option on every computer. God forbid someone discovers you spent two hours going through every photo of your ex’s new lover’s mother’s family vacation album from 2011 on Facebook.

RELATED: Paula leads ‘Crazy Ex-Girlfriend’ into fearless feminist territory

Rebecca and Valencia then take their Anna stalking mission to the next level. They go full “Thelma and Louise,” traveling up to Los Angeles, to meet her in person, and the wonderful hi-jinx reaches CIA level crazy. Overall, this episode is one of the highlights of the season, and viewers are left heading into the holiday winter break wanting more. How much longer will we have to wait until Paula (Donna Lynne Champlin) and Rebecca make-up? Is Paula’s marriage going to survive the pressures of law school? Will Anna and Josh last? Are White Josh (David Hull) and Darryl (Pete Gardner) still going strong? There’s so much we need to know!

Who Needs Josh When You Have a Girl Group?

“Crazy Ex-Girflriend” has only gotten better in Season 2, the songs more witty, and the storylines, ya know, more “nuanced.” Here’s hoping Karen gets to shuffled into the mix a bit more in 2017 — Weir’s unique humor steals every scene — and fingers crossed Sunil (Parvesh Cheena) sticks around even after Paula and Rebecca make peace. The three of them becoming a trio of besties would make for a spectacularly fresh and wildly entertaining musical number.

“Crazy Ex-Girlfriend” will return with new episodes on Friday, Jan. 6, at 9 p.m. ET/PT on The CW.

Posted by:Emily Bicks

Freelance writer in LA. Sometimes, I'm on camera. And sometimes I'm not. Twitter: @missbicks