Disney Junior is gearing up to premiere a new TV movie based on its series Elena of Avalor, Disney’s first princess inspired by Latin cultures and folklore. Elena of Avalor: Song of the Sirenas will debut on September 21 on the Disney Junior and DisneyNOW app.

In the special, Elena travels to Nueva Vista to reconnect with her cousin when she encounters mermaid-like creatures called sirenas. It features and all-star guest voice cast including Gina Rodriguez (Jane the Virgin), Edward James Olmos (Battlestar Galactica, Blade Runner, Miami Vice), Rita Moreno (West Side Story, The King and I), Prince Royce and Rosario Dawson (Sin City, Luke Cage) as sirenas.

Following the premiere, the kidcaster will also release a series of shorts titled Elena of Avalor: The Secret Life of Sirenas. Additional brand extensions for the storyline include a new storybook based on the TV movie from Disney Publishing released earlier this summer, as well as toys, dolls and roleplay set to hit shelves on August 1.

Craig Gerber is the creator and executive producer of the Elena of Avalor series, while Silvia Olivas serves as co-executive producer and story editor and Elliot M. Bour is co-producer and supervising director. Marcela Davison Aviles, the founder of The Chapultepec Group, serves as the show’s cultural advisor alongside Diane Rodriguez, co-founder of the theatre ensemble Latinas Anonymous and member of the National Council of the Arts. The show is a production of Disney Television Animation.

Elena of Avalor premiered in July 2016, with a third season commissioned in early 2017. The series is also incredibly popular on the consumer products side with more than one million dolls inspired by the show—and created by Hasbro—sold at the Disney store.