The 36-year-old actress, however, said it is too early to discuss anything, reported Contactmusic.
"It's still super-early days, and I don't know where that's gonna go - if it's gonna go anywhere at all," McAdams said.
The "True Detective 2" star is rumoured to take a lead role in the upcoming movie. There is no confirmation yet about the character she will play, but she will reportedly appear as Clea, Dr Stephen Strange's love interest.
In the comics, Clea is both a niece and close disciple of Dormammu, a master of dark magic who is also one of Strange's biggest enemies. She is a sorceress who possesses many of the same abilities as Strange.
The movie about the titular neurosurgeon doctor, who discovers the hidden world of magic and alternate dimensions, will open in US theatres on November 4, 2016.