Adam Lambert & Lil Nas X Party Together on Halloween - See Their Costumes!

Adam Lambert and Lil Nas X met up while celebrating Halloween!

The 40-year-old “Whataya Want From Me” singer and the 23-year-old “Montero” rapper partied together at Delilah nightclub on Monday night (October 31) in West Hollywood, Calif.

Lil Nas X went shirtless while wearing golden armor and horns on his head while Adam was dressed in leather with green hair.

Click inside to see the photo of them together…

“Halloween at Delilah,” Adam captioned a photo that he snapped with Nas inside the event.

Adam celebrated Halloween this year by going on The Witch Hunt concert tour.

“There’s a theme running through the shows,” Adam told E! News before his first show. “What I’ve done is I’ve gone through my catalogue and picked out the songs that fit this Halloween theme…I also picked out some amazing songs that I’ve loved over the years that also fit into this vibe and I think people are gonna really love coming to the show.”

Click through the gallery for more photos…