In "Hollywoodland," costume designer Mari-An Ceo recreated Katherine Hepburn's lavish gown from "The Philadelphia Story" for Abigail Spencer's Lucy.

The second and final season of “Timeless,” NBC’s time travel drama, embraces more inclusion and diversity, including encounters with abolitionist Harriet Tubman, suffragist Alice Paul, and blues musician Robert Johnson. This greatly expanded the challenges and opportunities for costume designer Mari-An Ceo, who especially enjoyed “Hollywoodland,” in which she got to recreate Katherine Hepburn’s lavish Greek goddess gown from “The Philadelphia Story” for star Abigail Spencer.

“The stories shifted and became more evolved [this season], but this was one of my favorites,” Ceo said. “Going into Hollywood, it felt like we were making a movie and dressed all the people that worked on movies. We made hundreds of background costumes. We were on the Paramount lot and, finally, we were shooting where the place actually was supposed to be.”

In “Hollywoodland,” the Lifeboat team of Lucy, Wyatt (Matt Lanter), and Rufus (Malcolm Barrett) travel to 1941 Hollywood to retrieve the stolen negative of “RKO 281” (“Citizen Kane”) before William Randolph Hearst can get his hands on it and destroy Orson Welles’ debut masterpiece. They sneak onto the RKO lot, where Lucy and Wyatt pass themselves off as a singing duo, and gain the help of actress/inventor Hedy Lamarr (Alyssa Sutherland).

For Ceo, costume designing “Timeless” was always a hectic time-crunch, but the wardrobe department made all of the clothes for the Lifeboat trio since renting was too hit and miss. “We go from a photograph, an idea, a sketch, a fabric. It gets made,” Ceo said. “But [Spencer] can go through any time period and wears it well.”

Paul Drinkwater/NBC

The costume designer often relied on Spencer for ideas, and the actress’ brainstorm for “Hollywoodland” was riffing on Hepburn. “I’m obsessed with Katharine Hepburn and ‘The Philadelphia Story’ is one of my favorite films. And one of my dreams was to wear the famous white dress with the gold sequin beading,” Spencer said.

The white chiffon gown was made for Hepburn by Adrian to emphasize her lean figure and statuesque Greek stature. “I asked Mari-An if we could make it and she was able to make it happen,” added Spencer. Of course, they sidestepped the historical fact that “The Philadelphia Story” was made at MGM in 1940, which made it a stretch for Lucy to steal it at RKO.

“We had to find where the real dress was, then get better pictures of it to replicate it,” said Ceo. “There were a couple of different versions of it and we found them at two museums. The one we made was silk.”

For Spencer, the beading felt like armor. “But it was such a good dress for Lucy to wear in that big moment when she sings ‘You Made Me Love You (I Didn’t Want to Do It),'” she said.

With the presence of Lamarr, the episode was able to explore additional female empowerment and allude to the Hollywood starlet becoming a tech trailblazer. The Austrian-born actress (“Dishonored Lady,” “Ziegfeld Girl”) actually invented a torpedo guidance system during World War II, whose tech was responsible for many of the digital comforts we enjoy today (cellphone, Bluetooth, GPS). Lamarr was the subject of last year’s doc, “Bombshell: The Hedy Lamarr Story.”

“The actress [Sutherland] came in for a fitting and I was inspired by a dress that I thought she’d look amazing in,” said Ceo. “The color was a Hedy color, green with pink on the inside, but I didn’t copy a dress.”

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