It turns out Barbra Streisand is a dangerous woman.

The legendary EGOT winner is currently on the road in support of her latest release, Walls. During a recent Chicago tour stop, she brought out a very special surprise guest, pop star Ariana Grande, to help her belt a disco classic.

Ariana fans knew something was up when Barbra posted a photo on Instagram of her and Ariana's pedicures with the caption "Made a new friend..."

At her August 6 show, Barbra surprised the audience by bringing the "Thank U, Next" singer onstage to help her sing "Enough Is Enough (No More Tears)," which Babs originally recorded with disco queen Donna Summer.

There were plenty of tears left to cry when Ariana and Babs took the stage together, causing fans to freak out IRL and online:

Stop what you're doing and check out this classic moment between two divas in the video below.

What other surprise guests do you dream of Babs inviting onstage for a duet?