WATCH: Liz Gillies Chats Collab with Bestie Ariana Grande and Their Iconic "Showgirls" Costumes

Actress and singer Liz Gillies visited the world-famous Empire State Building Observatory to flip the switch in a lighting ceremony to honor World Smile Day, in partnership with Smile Train, on Oct. 4.

After she flipped the iconic switch and toured the building's immersive museum and unmatched Observatories, Liz sat down to discuss her Smile Train ambassadorship, her bestie Ariana Grande, and her new single.

See the full video below!