The 23-year-old actress added old Hollywood glamour in a silk Oscar de la Renta creation, which she teamed with a diamond ear cuff as she arrived at the Ziegfeld Theatre.
She also completed her gothic-inspired look with black nails, bright red lipstick and grey suede heels.
Watson, who recently admitted that she missed an Oscars after-party for a slice of pizza and a nap, was joined by co-stars Douglas Booth, Ray Winstone and Jennifer Connelly, who wore a black leather Louis Vuitton dress.
Connelly was accompanied by actor husband Paul Bettany, while Winstone was with actress daughter Jaime and wife Elaine.
The movie's lead Russell Crowe was greeted by 50 Cent on the red carpet, who proceeded to take a selfie with the cheerful Gladiator actor.
Director Darren Aronofsky, accompanied by a female guest, was also in attendance.
Aronofsky's biblical epic is expanded from its original tale of Noah (Crowe) receiving apocalyptic visions and battling the forces of Tubal-cain (Winstone) as he and his family fight to survive the coming flood.
Logan Lerman, Nick Nolte, and Sir Anthony Hopkins also feature in the cast, based on a script by Aronofsky and his The Fountain co-writer Ari Handel.
Noah will be released on March 28 in the US and April 4 in the UK. Watch a trailer below: