Life&Style is reporting that "Mad Men" star Jon Hamm and his girlfriend, actress-director Jennifer Westfeldt were recently robbed in London when they were visiting the city to promote their new film, Friends With Kids.

A source tells the magazine, "They were dining at a restaurant and Jennifer's purse was snagged by someone. That person took the hotel key in Jennifer's purse, which had the hotel name on it, and robbed their room. They had to contact the police, it was horrible."

When asked about the event earlier this month, Westfeldt -- who wrote, directed, and starred in the movie -- said the incident was still under investigation. "What a mess," she said.

One thing that went smoothly was how the couple worked together during filming. Hamm plays a part in the film and helped produce it. Westfeldt told Life&Style that the experience brought them closer. "Some people would say they could never work with their partner, but we found it incredibly bonding," she said. "Independent films are so stressful; it feels like pushing a boulder up a hill. So it felt great to have a partner in crime."

The two have been together since 1997, and while they do not have children, Westfeldt told the Huffington Post that she and Hamm are fascinated to see how the process affects their friends. "We wrote the film in response to so many of our friends becoming parents, and it's this incredibly profound transition," she said. "You are sort of watching your friends and losing them one by one because they kind of go underground for a while when they are new parents.”