[Warning: The following article and interview contain spoilers about the series finale of “Grace and Frankie.”]

Costume designer Allyson Fanger has worked on all seven seasons of Netflix’s “Grace and Frankie,” and her looks for the title characters played by Jane Fonda and Lily Tomlin are immediately recognizable. But in the seventh and final season, the characters change as they walk off into the sunset – figuratively and literally – and so did Fanger’s designs. Her past work on the series has earned five consecutive Emmy nominations for contemporary costumes. Watch our exclusive video interview above.

For the past few years, Fonda has been sporting her natural gray hair, so now her character Grace does as well in the final batch of episodes. “We really had to change her whole palate,” says Fanger of how to accommodate the actress’ hair color into her wardrobe choices. The buttoned-up character had once started out “very, very neutral,” but as the designer explains, “Over the seasons...