The idea that Mikkelsen isn’t playing a straight up villain sort of makes sense in the scope of Doctor Strange.
We have known for quite some time that he is playing the villain in Doctor Strange, but according to Mads Mikkelsen he isn’t a villain in the traditional sense.
He will also be the bad guy in the upcoming Doctor Strange, but we don’t know who he is playing.
Mikkelsen also commented a bit about what we can expect in terms of tone from Doctor Strange.