Sean Grandillo is an American actor, singer, and musician originally from Aurora, Ohio. On Broadway, he starred as Dwayne in The Lost Boys at the Palace Theatre. He made his Broadway debut in the Deaf West Theatre revival of Spring Awakening at the Brooks Atkinson Theatre, where he originated the role of the Voice of Otto while also serving as the production's bassist and conductor. His national tour credits include Curly McLain in Oklahoma! and the title role in The Adventures of Tom Sawyer.
On screen, Grandillo's television credits include a series regular role on MTV's Scream, the lead in YouTube Premium's Youth and Consequences, and recurring roles on Rise, The OA, The Real O'Neals, Condor, and Blue Bloods, among appearances on Law and Order: SVU and NCIS: New Orleans. His film credits include King Cobra and Summoning Sylvia. As a recording artist, he has released the EP Why Is It so Hard to Change and the album Necessary Trouble. He studied musical theatre at Ithaca College.