This year’s Costume Institute show is part of the Met’s larger 150th-anniversary celebration, and its theme, fittingly, is about “fashion and duration.” In a moment where fast fashion reigns and today’s trends feel old tomorrow, “About Time” speaks to the designs and silhouettes that both stand the test of time and evoke specific moments in history. In this 15-minute video, Andrew Bolton, the curator in charge of the Costume Institute, walks viewers through the exhibition, explaining its ideas, organization, and the interplay of 125 fashions—from 1870 to 2020. —J.V.