Lily Collins knows a thing or two about a quick costume change.

Participating in a conversation called “Emily in Paris: The Magic Behind the Scenes” at the Paley Museum on Sept. 17, Collins pulled back the curtain to reveal how her wardrobe comes to life in Darren Star’s hit Netflix show — which has become known for its colorful fashion as much as its dramatic love triangles.

Now in Season 4 and renewed for Season 5, each chapter of the romantic dramedy series showcases a fresh slate of bold outfits in a range of hues, textures and silhouettes, curated by the hand of costume designer Marylin Fitoussi.

Lily Collins and Ashley Park in Season 4 of “Emily in Paris.”

Collins, who plays the titular American expat and marketing maven, shared at the panel, “Every season starts with two days of eight-hour fittings. So I have 16 hours of fittings — a record-breaking 81 looks in those two days this year. And some are commissioned, some are vintage, some are from collections of a time-gone-by, some are unknown designers that [Fitoussi] found in her DMs, some are well known designers. The list goes on and on.”

Whether she’s wearing a miniature pink cardigan, a monochrome blue suit or an avant-garde dress, audiences can bet that Emily will be arriving in style to her business meetings, romantic rendezvous and café debriefs with her best friend Mindy (Ashley Park). And the team never falters when it comes to Emily’s shoes, with her footwear encompassing white Nodaleto pumps, black leather boots and plenty of styles in between.

Lily Collins in Season 4 of “Emily in Paris.”

Collins, who was joined at the panel by her castmates as well as Star and director Andrew Fleming, revealed that costuming is a team effort on the set of “Emily in Paris.”

“Some are pieces from my wardrobe. We all bring our own ideas. We bring people, we bring family heirlooms, we bring gifts we want to wear,” the actress, who wore a pair of stunning Versace Slice Pumps to the event, said. “And [Fitoussi] has such an identity for each of us that we have added to throughout the years. You can clearly go into a room and go, ‘That’s definitely for Mindy, that’s definitely for Bruno, that’s definitely for Samuel, that’s definitely for Philippine.’ You know who everyone is so well this time in a fourth season…We know ourselves even better. And she’s so open to having that collaborative nature with us.”

Philippine Leroy-Beaulieu, who plays Emily’s take-no-prisoners boss, emphasized that the fashion in the series is not just a frivolous feast for the eyes. She discussed how wardrobe can serve as a mode of communication with the audience: “We want the public to feel for the character, not only see…For me it’s about what you want to show the public without telling them in a way — the way a coat moves, the way that color has meaning, it’s sort of a subliminal language you put together with costumes.”

Park expressed a similar sentiment. Citing an example of a meaningful wardrobe moment, she unpacked the thought process behind a dress she wore in the Season 5 finale, which was screened at the event. Dealing with heartache and a setback in her music career, Mindy is walking with Emily in Rome when her friend’s words inspire her to finish writing an emotional ballad and break into song in public.

Lily Collins as Emily, Ashley Park as Mindy in episode 309 of Emily in Paris.

“There were so many cut-outs [in the dress] so she was extremely vulnerable in that situation — but it was this bold and confident red color that showed that she was in herself. And the texture was extremely structured and confining, but also very fluid and versatile,” Park said. “Everyone has examples of that kind of thought that’s put into [wardrobe]. And I think that’s the special little sauce that is in this show. It’s not just fashion for fashion’s sake or costumes, there’s a lot of heart and genuine thought that’s put into, ‘What story are we telling with these costumes?’”