Marvel had been pursuing him for the role early on. Michael Douglas was initially cautious to pursue the role, but he reportedly had a change of heart over the holiday season. With the actor portraying Hank Pym, the original Ant-Man in the Marvel comics, this likely means that Paul Rudd is playing Scott Lang, who took over the Ant-Man mantle in the comics.
Here's what producer and Marvel Studios president Kevin Feige had to say about the casting in a statement.
"With Hank Pym's rich history in the Marvel Universe, we knew we needed an actor capable of bringing the weight and stature to the role that the character deserves. We felt incredibly relieved when Michael Douglas agreed to step into the part with the charm and fortitude he brings to every character he inhabits, and couldn't be more excited to see what he will do to bring Hank Pym to life."
No story details have been confirmed. However, last month, director Edgar Wright released a photo from an episode of the animated series The Avengers: Earth's Mightiest Heroes, "To Steal an Ant-Man", which centered on Scott Lang stealing the original Ant-Man equipment from Hank Pym, to commit crimes. The episode is is based on the comic book Marvel Premiere #47, which also featured Luke Cage and Iron Fist, characters who are getting their own Netflix TV shows in the near future.
Michael Douglas won a Golden Globe award last night for his portrayal of Liberace in the HBO TV movie Behind the Candelabra. He also recently starred in Last Vegas, and he will next be seen in And So It Goes... later this year.