Kiernan, who is playing the main role of Sabrina Spellman, wore a two-piece silver number with ruffles, orange, and yellow details on her dress' shoulder straps and hem.
Ross opted for an all-blue outfit, including a button-down and dress pants with black shoes. The standout of his look was his new brown hair, which he dyed for the role after Kiernan dyed her hair blonde.
The stars joked with each other on the carpet, with the Chilling Adventures of Sabrina actress pretending to be scared of something Ross said.
Kiernan, 18, also took the phone of a fan and posed for a selfie with the crowd.
The Teen Beach Movie actor, 22, followed suit and posed with some fans as well.
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