The actress – who played Niki Sanders and Tracy Strauss on the superhero series – was chic and elegant in a fitted cream and black dress at a Pampers dance event held at the Children's Museum of Manhattan on Wednesday, 20 August.
She looks gorgeous, doesn't she?!
Ali is expecting her second child with husband Hayes MacArthur. They are already parents to son Theordore, who was born in 2010.
The couple married at Hayes' home in Maine in 2009.
Ali currently appears in spy drama TV show Legends alongside Sean Bean.
Announcing her pregnancy earlier this year, she admitted she had to be a "covert spy" herself and try to hide her pregnancy on set when she first discovered it.
"It's so exciting. It's such a scary time and I've been trying to hide it as much as you can, and when you're in the public eye it's really scary in the beginning... I was still shooting my spy drama … I had to be a covert spy in my real life, too, so I'm wearing blazers and push-up bras and everything you can do to distract."
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