Keira Knightley and Elisabeth Moss joined forces for the debut of their new play, The Children's Hour, in London yesterday. The duo changed out of their costumes and into cocktail dresses for the afterparty, where they posed together for photographers. Keira, who split from her longtime boyfriend Rupert Friend recently, has been busy in London while she works on the stage production. The actress was recently spotted on the arm of a male friend, but she and Elisabeth seemed happy to enjoy a girls' night out. Keira has also been hanging out with her fellow single lady Sienna Miller, whose breakup with Jude Law was just announced this week.