“I have all kinds of theories about her backstory,” says actor Donna Murphy of her Disney alter ego: the sinister Mother Gothel in Tangled.

With music by Alan Menken and lyrics by Glenn Slater, the songwriters gave Murphy plenty to play with in terms of all the different ways to be evil—“all these different tactics,” as she puts it in our exclusive interview.

The take on the classic Rapunzel fairytale paints Mother Gothel as the evil witch who stole Rapunzel from her royal parents because of Rapunzel’s healing powers, which also grant eternal youth and beauty. In her song, “Mother Knows Best,” Mother Gothel must do everything to convince Rapunzel that she’s better off staying in the tower than going off into the world. As Murphy shows us in the video above, she learned more about the deviousness of the woman as she recorded her voice and the song—finding new ways to use her belt and her delicate coloratura to serve the character.

Watch: DONNA MURPHY GETS EMOTIONAL DESCRIBING HER TAKE ON HELLO, DOLLY!’S DOLLY LEVI

Murphy and her fellow Disney leading ladies—Jodi Benson, Paige O’Hara, Lillias White, and Judy Kuhn—gathered to go behind the music with Menken as they filmed a bonus special “Alan Menken and His Leading Ladies” for the 30th anniversary celebration of the The Little Mermaid and the film’s release into the Walt Disney Signature Collection.

Watch our full interview with Murphy above, and be sure to catch the full bonus feature “Alan Menken and His Leading Ladies.” Available on digital, 4k Ultra HD, and Movies Anywhere February 12 and on 4k Ultra HD and Blu-ray February 26. The Little Mermaid also includes new bonus features inside the original recording sessions; a new installment of Stories From Walt’s Office, featuring “Gadgets & Gizmos” Disney kept in his office; a “#TreasuresUntold” special, revealing secrets about the original movie; DCappella’s fresh music video of “Part of Your World”; sing-along mode; and classic bonus features like deleted scenes, audio commentary from directors Ron Clements, John Musker, and Menken. Plus, only available on digital, three additional hours of bonus features and “Part of Your World” – A 30-Year Retrospective where Menken and Benson talk about finding Ariel’s voice, the peak of Disney “I Want” songs, and more.