Her show-stopping number is "Losing My Mind," a song Staunton says Sondheim encouraged her to take literally.
Imelda Staunton dazzles as 'Follies' hits cinema screens →
"This song is designed so that those towns never feel forgotten again," he said. "I cannot wait for Puerto Ricans to hear Luis Fonsi sing the name of their town or J.Lo to sing the name of their town."
J.Lo, Estefan, Miranda and Fonsi sing to help Puerto Rico →