Shawn Mendes may be good at singing, but he's not good at lying as he was exposed in a lie detector test for his true feelings with Taylor Swift's beau, Joe Alwyn.

According to Us Weekly, the Canadian singer sat down with Vanity Fair for a lie detector test where he was asked numerous personal questions.

In the beginning, he nervously said that he "can't stop smiling," and "something weird is happening." (watch the full video below)

When asked whether he approved of Swift's current boyfriend, he mentioned that he never personally met Alwyn, but "he looks like a sweet guy."

The operator immediately called him out, telling him he was not telling the truth and he was "being deceptive."

Camila Cabello's boyfriend later clarified that he's not telling the truth "a little bit" because he thinks Alwyn has a "villain look about him."

He added that Alwyn looks like a nice guy, but he's afraid that any movement could "turn into a villain."

In addition, he said the actor has "really blue eyes," and he's having a hard time trusting people with that trait because he trusts people with brown eyes more.

Aside from Alwyn, Mendes was also asked questions about Harry Styles, Justin Bieber, John Mayer, and his current girlfriend, Camila Cabello.

Mendes later gave a brief background on his friendship with Swift after they toured together in 2015 for her "1989" world tour.

He mentioned that he's always asking her for advice when it comes to music, and they regularly text each other.

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Taylor Swift, Joe Alwyn Relationship Timeline

According to Elle, Taylor Swift and Joe Alwyn allegedly first met at the 2016 Met Gala. Fans allege that the song "Dress" from her record "Reputation" might refer to their first encounter.

In 2017, a source previously revealed that the pair had been dating for a few months at the time, and their friends and family approve of their relationship.

They have been very private about their relationship ever since, but both of them are always caught by the paparazzi on numerous occasions.

Then in 2020, Swift opened up about Alwyn in her Netflix documentary, saying, "We decided together we wanted our relationship to be private."

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