Kendall Jenner Gave Hailey Baldwin a Lie Detector Test About Justin Bieber for Carpool Karaoke

And the results were hilarious.

What happens when you put Kendall Jenner, Hailey Baldwin, and a lie detector test together in a car? A whole lot of hilarious honesty.

In a new trailer for an upcoming episode of Carpool Karaoke: The Series, the models alternate between the normal road-trip activity of singing along to their favorite songs and the decidedly not-so-normal activity of subjecting each other to a lie detector test. Awkward for them, sure, but amazing for the rest of us.

The clip starts with Kendall asking Hailey if she likes her hair up in a high ponytail, which she says she does (luckily, it turns out to be the truth). From there, though, things started to get juicier. Hailey kicks it up a notch by asking her friend, "Have you ever created a fake Instagram to look at what your ex-boyfriend is doing?” Kendall starts laughing and reveals, "You know the answer to this! Yes!” Sadly, neither model spills details on the account or who the ex actually was.

The Keeping Up With the Kardashians star fires back with her own hard-hitting question, asking her newly engaged friend about what her famous fiancé really thinks of her. "Does Justin think I'm cool?" Kendall asks. Hailey pauses a few uncomfortable seconds before laughing and assuring her friend, "Of course!"

At that point, the lie detector reveals that Hailey was, in fact, telling a lie. LOL.

Though Justin Bieber may not necessarily think Kendall is "cool" (at least according to the lie detector test), the model is still deeply supportive of the engagement between her two friends. When Jimmy Fallon asked Kendall if she was happy about the news on a recent episode of The Tonight Show, she replied, "Yeah, whatever makes them happy, I’m happy. I’ve been friends with both of them for a very long time. So everybody’s happy, and that makes me happy."

Thankfully, there were no hard feelings about the lie detector test, and the girls finish out the spot singing some old-school Panic! at the Disco together, which is a far better road trip activity, anyway.

Let us slide into your DMs. Sign up for the Teen Vogue daily email.

Want more from Teen Vogue? Check this out: Bella Hadid and Hailey Baldwin Keep Wearing This $27 Gold Chain and It’s Still Available

See the video.