The 32-year-old, who plays Mercedes McQueen in Hollyoaks, wore a pillar-box red latex pencil dress by designer Atsuko Kudo.
It seems Metcalfe has been taking style tips from Kim Kardashian and Rita Ora, who've also been spotted out in similar styles by the designer.
If you're a fan of her dress, you're in luck - it's available to buy for £282.50 from the Atsuko Kudo website.
Did Metcalfe pull it off? Have your say in our poll:
Check out all the snaps from the red carpet below: