The 'Only Murders in the Building' costume department has gone through at least 100 scarves for Martin Short's character. His best one was found hidden in a thrift store.

• Season three of "Only Murders in the Building" is now streaming on Hulu.
• Insider spoke with Dana Covarrubias, the show's Emmy-nominated costume designer, during production.
• She shared that a scarf Martin Short's character wears this season was a thrift-store find. 

Much has changed in the world of "Only Murders in the Building" for season three — new characters and a fresh mystery, for starters.

But the dedication Martin Short's character has to wearing scarves? That remains exactly the same.

Ahead of the show's latest season, Insider spoke with Dana Covarrubias, the Emmy-nominated costume designer who leads the show's wardrobe department, about dressing stars like Short, Steve Martin, and Selena Gomez.

Covarrubias said her team has gone through at least 100 scarves for Short's character Oliver Putnam since the show began. But there's one featured in episode two of the current season that stands out.

"I was at a thrift store upstate in the Hudson Valley, and I just happened upon this beautiful scarf," she said. "It's this beautiful black-and-cream piece and it has the New York City skyline on it. I gasped when I saw it. I was like, 'It's perfect.' Those finds are very exciting."

Equally as exciting as finding the scarf was actually being able to use it onscreen.

"We're a mystery show, so we have stunt doubles, blood, all that stuff — and we often need doubles of everything our characters wear, which limits you a little bit," Covarrubias said. "But we also have some scenes where we don't we doubles, so when we find a beautiful piece like that, we can use it."

It was also Oliver's character growth this season, she said, that gave her team the opportunity to dress him in something a little more flashy.

"With Oliver this season, he is fully stepping into himself and becoming this theater director," she said. "He can go bigger  — with pattern, color, style."

Still, she didn't want to make him "too fancy." After all, Short's character is a working man on the go.

So that's where Covarrubias' expertise came in. Rather than dressing him in a restrictive blazer, for example, Short would wear a chore coat or vest with a scarf.

And to make his looks more fun, she added brighter colors and bolder patterns to his outfits — something they might not have done in previous seasons.

"I've said this every season: Marty's really kept me grounded, which is hilarious because he's so outgoing," she said. "You would think he would want to be flamboyant with his costumes as well. But he's really wonderful at balancing me."

"But this season, I got to sneak a couple of little things in that were a little more wild," she continued. "In season one, he maybe would've been like, 'Dana, what are you thinking?' But this season, he didn't even blink an eye. He was like, 'Yeah, sure! That's Oliver.'"