A big night to take a big step (and repeat).
The couple attended an annual viewing party hosted by Mercedes-Benz -- Hamm is a brand ambassador -- in Beverly Hills on Sunday, March 27. They later also attended the Vanity Fair party, stopping on the red carpet.
Having reportedly first met while filming the "Mad Men" series finale in 2015, a source confirmed to Us Weekly in June 2020 that the actors, were indeed, an item -- Hamm's first serious romance after announcing the end of his nearly two-decade relationship with screenwriter Jennifer Westfeldt in 2015.
"With great sadness, we have decided to separate, after 18 years of love and shared history," read a joint statement released from the pair at the time. "We will continue to be supportive of each other in every way possible moving forward."
A few years after Hamm admitted to InStyle that being single "sucks," he was spotted out with Osceola. Nothing like a joint appearance on Hollywood's biggest night to make things officially official.