The actor, 33, posed as she arrived at the London awards show in a floor-length gown with pearl caged detailing at the front.
Her dramatic ensemble, which also came with a voluminous bow at the back, was created by Australian designer Tamara Ralph.
She kept the rest of her look simple, with a sleek up-do, minimal jewellery and Charlotte Tilbury make-up.
James, who is to appear in the upcoming film What's Love Got To Do With It?, wasn't the only star to wear white for the glamorous evening, which is being held at the Royal Festival Hall.
Geri Horner also opted for the chic shade to attend the star-studded ceremony alongside her husband Christian Horner.
The Spice Girl, 50, wore a silky, off-shoulder floor-length dress, which she accessorised with an up-do and silver jewellery.
Posting a picture of her gown – created by Halfpenny London – on Instagram, many fans suggested that the outfit looked rather bridal.
Also choosing white was Emma Thompson, 63, who looked chic in a white trouser suit with a matching coat draped over her shoulders.
Similarly, Richard E Grant – who was chosen to host the 76th film awards ceremony – made a dramatic entrance in a sweeping, floor-length white cloak with a monochrome ensemble underneath.
The actor, 65, described himself as the night's "host, fashion icon..." wryly adding, "I've also done a bit of acting on the side".
Meanwhile, Florence Pugh brought the colour to the evening with a bright orange dress, featuring a fishtail train.
The actor, 27, also gave her look a punk-style edge with a spiky up-do and her trademark septum piercing.
Last month, James wowed on the Golden Globes red carpet in Los Angeles a cut-out red gown by Versace.
She also wore on her lips a cult £27 nude lipstick by Charlotte Tilbury, which Salma Hayek and Jessica Chastain also used.
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