After headlining a successful Night 2 at Coachella, Lady Gaga, alongside co-star Bradley Cooper, will be filming scenes for their upcoming movie A Star Is Born in Indio. On Sunday, festival goers were notified on Coachella’s mobile app that they had the chance to be in a scene for the upcoming Cooper-directed musical, according to the Los Angeles Times.

Based on William Wellman’s 1937 movie, A Star is Born is about a singer (Lady Gaga) who falls in love with an aging rocker (Cooper) who launches her successful career as his own is in a downward spiral. The film was remade in 1954 with Judy Garland and 1976 with Barbra Streisand, in what would be Gaga’s role.

Filming will take place on Tuesday, April 18 and Wednesday, April 19 and the scenes will portray a country western concert. Attendees must be 18 years or older and fans are asked to dress in western-themed attire. “All you Monsters that can attend should get decked out in your most comfortable denim & boots, throw on a Stetson (leave those pink Joanne hats at home) and come out to show your support!” reads the announcement.

It costs $10 to attend and all proceeds will be going directly to the singer’s Born This Way Foundation. Warner Bros. also tweeted out information on how to sign up.

Earlier this week cinematographer Matthew Libatique also shared a photo from set, “Always a thrill when you finally get to shoot in prep,” read the caption, as production is underway.

Always a thrill when you finally get to shoot in prep. I don't even mind my new name. #cameratests #ASIB

A post shared by libatique (@libatique) on

The latest version of the script was written by Eric Roth (Munich, Forrest Gump); previous versions were written by Cooper and Will Fetters. Cooper is producing with Billy Gerber, Todd Phillips, Lynette Howell Tayor and Jon Peters, with Basil Iwanyk on as executive producer.

A Star Is Born is slated to be released on September 28, 2018.