As Peggy Olson and Pete Campbell on AMC's Mad Men, Elisabeth Moss and Vincent Kartheiser have had a somewhat tumultuous onscreen relationship. Offscreen, though, Moss has nothing but great things to say about her costar -- and his new fiancee, Alexis Bledel.
"They are such a yin and yang! I love them both!" the actress gushed to Us at the March 20 Mad Men season six premiere screening in Hollywood, Calif. "I have known Vinny for 12 years, and Alexis -- I'm kind of obsessed with her. She's the sweetest!"
As Us Weekly revealed earlier this week, Kartheiser, 33, proposed to girlfriend (and former Mad Men love interest) Bledel, 31, a few weeks ago. "They are so cute together," a source told Us of the spouses-to-be.
Moss agrees. "I've never seen Vincent like this," she said. "They are so happy. It's really cool!"
Of course, Kartheiser isn't the only Mad Men star to experience a huge life event over the course of the show's nearly six-year run. Moss herself has gone through several changes, including a short-lived marriage to Saturday Night Live comedian Fred Armisen, and she's a better actress for all of them.
"I've had seven years and most of my twenties [on the show] -- and, you know, your twenties are a very big, formative time in your life. I've had things happen, and to bring that to Peggy as she's grown up has been really cool," the 30-year-old star told Us.
In fact, everyone in the cast has evolved since the show's debut in 2007. "We've had weddings, divorces, babies, all kinds of things! It's like a family, it really is," Moss raved. "We've all been through so many different stages of our lives, and we've literally seen every single person in the cast go through so much personally and professionally. It's incredible to watch people grow...Everyone talks to each other, and we're all supportive of each other, seriously."
This article originally appeared on Usmagazine.com: Elisabeth Moss: I'm "Obsessed" With Vincent Kartheiser's Fiancee Alexis Bledel