It's official: The doctor is in for "Thor 2."

In 2011's "Thor," Swedish actor Stellan Skarsgård played Dr. Erik Selvig, who fell under the control of the evil Loki (Tom Hiddleston). He was freed from the villain's spell in this summer's "The Avengers." Now, he'll re-appear in "Thor 2."

Skarsgård told Hey U Guys that he'll start shooting the sequel in August. It's unknown, however, how big of a role Selvig will play in the proceedings. 

He's reuniting with Thor himself, Chris Hemsworth, who is returning as Marvel's Norse god of thunder. Natalie Portman is also coming back as Jane Foster. 

"Casino Royale" vet Mads Mikkelson (playing an unnamed villain) and "Chuck" star Zachary Levi (stepping in as Fandral) are also joining the cast. Alan Taylor ("Game of Thrones") is directing, replacing the first installment's Kenneth Branagh.

Besides the Marvel films, Skarsgård recently co-starred in Lars von Trier's "Melancholia" and David Fincher's "The Girl With the Dragon Tattoo." He'll soon reunite with von Trier and actress Charlotte Gainsbourg for the two-part "The Nymphomaniac," which he cheerfully describes as "very Lars von Trier...It's a porno film."