The actress Anne Hathaway’s historical California cottage

When the actress Anne Hathaway and her husband Adam Shulman hired Pamela Shamshiri to renovate and restore a newly acquired weekend hideaway in Southern California, the design principal of Studio Shamshiri embraced the opportunity to flip the script. Instead of going for theatrical drama and Hollywood glamour, she gave the house an elevated version of the curated California-casual elegance she had fostered as a founding member of the much-lauded firm Commune Design, which brought organic modernism and artisan crafts to fashion boutiques and the Ace hotels in Palm Springs and downtown Los Angeles. She also proposed a narrative that would reflect the property’s history and her thespian clients’ personalities.

“What if Wes Anderson bought a Swiss chalet in Southern California and Yves St. Laurent was coming to stay?” Shamshiri asks. “What would that look like?”

The house was, in fact, designed by architect Myron Hunt in what Shamshiri describes as a “California Arts and Crafts–Swiss chalet mash-up” and built in 1906. “Fun fact: Myron Hunt is known for designing the Huntington Library and the Rose Bowl stadium, in Pasadena,” Shamshiri notes. The 3,500-square-foot, two-story residence has three original stone fireplaces, three bedrooms, four baths, a music room and a secret library. Over time, Hunt’s structure has received add-ons, including an entry and a dance hall, constructed in 1922, that Shamshiri transformed into a large music room equipped with a piano and back-to-back sofas that anchor two seating areas for large gatherings. “The property serves as a retreat from the city in which to host family and friends,” she explains.

As is often the case in older homes, the kitchen needed to be “completely demoed,” Shamshiri says. It was reconfigured to flow into a green, mural-wallpapered indoor breakfast room flanked by two outdoor entertaining spaces. “It might be my favorite spot in the house. The scale is so nice, and you sit surrounded by views from windows on three sides,” says the designer, whose client list includes musicians Beck and Kaskade, actor Seth Rogen and jewelry designer Irene Neuwirth.

Considering its age, the structure’s bones were in “amazing condition,” Shamshiri says. “The house is primarily made of walls and woodwork in Douglas fir, which is irreplaceable and has aged beautifully over the years. So, there are a lot of woody moments around the house.” The designer added board and batten to rooms that didn’t have wood paneling and moldings, painting them white along with vibrant colors like dreamy pink and vivid green. “We were honest with the restoration by paying homage to the past but not duplicating it,” she says.

Having worked together on another home, Shamshiri and the couple collaborated comfortably on this second project. “We share common interests, like collecting vintage, as well as a love for fashion and similar values in historical preservation efforts,” says the designer, who lives in R.M. Schindler’s 1947 Lechner house, in the Hollywood Hills. “Our approach was to honor the era that this house was built in, the culture and the architecture. We always start with a heightened sense of a place, then layer in the inhabitants and their collections.”

The couple is “crazy about collecting design,” she says, with a particular fondness for Italian mid-century furniture, the work of Jacques Adnet, Art Deco objets d’art and contemporary art. Shamshiri accommodated this predilection in her decor, also incorporating custom pieces of her own design, made-in-America items from BDDW and Sawkille Co. and antiques and vintage finds sourced online. “I can’t imagine doing a project without 1stdibs,” she says, “and I love that you can localize the search.”

The result is a cozy but thoroughly cosmopolitan mix of Scandinavian, French, English, Viennese and American design. “How objects dialogue is forever a mystery,” Shamshiri says. “You never really know until you see them together. But when the proportions and textures are exactly right, you can have an English leather chair, a Jacques Adnet desk, a Royère-inspired sofa and a Frank Gehry side table all in one room. It’s like a get-together where everyone speaks a different language but they all get along famously.”