Lauren Jauregui & Ty Dolla $ign Channel Harley Quinn & Joker at Halsey's Halloween Bash!

Lauren Jauregui and Ty Dolla $ign dress up as Harley Quinn and Joker at Halsey‘s Halloween Party!

The Fifth Harmony singer and her boyfriend attended the event held at The Majestic Downtown on Friday (October 26) in Los Angeles.

PHOTOS: Check out the latest pics of Lauren Jauregui

“Daddy’s Lil Monster👅👅👅,” Lauren captioned the Instagram slideshow below. “Harley Quinn & The Joker take Gotham City🍸 … New song #Expectations out now too if you’re looking to get in a Halloween vibe(; #linkinbio LaurenJauregui.com.”

“Zad and Mom 😈,” Ty added.

They were joined by Adam Lambert, who dressed up as a devil.