Near the end of the first act, the eponymous character is told to forget everything he thinks he knows. That is not necessary advice going into Doctor Strange, as it manages to weave enough superhero film tropes in to remain familiar, while using the unique nature of the source material to make something just different enough.
Gifted neurosurgeon Stephen Strange (Benedict Cumberbatch), after a traumatic car accident, travels to Nepal, chasing the rumor of a mysterious healer who can restore the nerve damage to his hands. What he finds is a secretive cadre of sorcerers operating under the guidance of the mysterious Ancient One (Tilda Swinton) who agrees to take him on as a student. As he excels in his studies, the purpose of this group is revealed to him and he must aid them against their greatest threat in the form of the renegade sorcerer Kaecilius (Mads Mikkelsen).
By now we've done enough of these superhero origin stories that loosely follow the hero's journey framework, so you roughly know what you're in for. The second act is devoted almost entirely to world-building (or should I say worlds) and since these characters operate literally and figuratively on a different plane than the rest of the MCU, there's plenty to go into without having to retread any ground Marvel fans have already repeatedly traversed. The aesthetics and effects do a great job of evoking Steve Ditko's artwork without seeming dated or more out of place than they're supposed to be. The action is entertaining, but with everyone's abilities so vaguely defined, it's difficult to build a lot of dramatic tension.
It does seem a bit odd that when Stephen is first introduced to the supernatural, he would express as much skepticism as he does. In a world where giant holes dump alien invasions and a Norse God is a public figure, you would imagine the intelligent would keep an open mind. One notable diversion from the typical superhero formula, the final showdown is managed in a way that breaks away from the norm (fighting a gang of faceless mooks then the big bad) and is much more fitting for this story.
Benedict Cumberbatch as Strange is probably the biggest Marvel Cinematic Universe casting no-brainer to date. The secondary characters are all solid. Strange's former medical colleague Christine Palmer (Rachel McAdams) doesn't have a whole lot to do, but she serves as a recurring presence in Strange's life that shows the juxtaposition of where he came from and where he's going. Mordo (Chiwetel Elijofor) and Wong (Benedict Wong) both function as deliverers of exposition and stoic foils to Strange's brashness. Mads Mikkelson gives us a sufficiently motivated and ruthless villain, but there's not a whole lot to him and his relationship to the other characters is left mostly unexplored. A relatively weak villain is a common occurrence in the first entry in MCU series, and given all the world building and characters they need to introduce and flesh out, it's mostly excusable if not for the fact that we know just how good at this sort of thing he can be if given enough room.
The big white elephant in the room though, is Tilda Swinton as the Ancient One. It's not that I automatically disapprove of changing a character's race in an adaptation, but given the nature of the character, it would have been nice to see an Asian actor get this chance to shine and lend a little more authenticity to the setting. That notwithstanding, Swinton does a fine job making the character mysterious and even vulnerable at times despite all her power.
Reviewing Marvel Cinematic Universe films is paradoxically easy and difficult, mostly for the same reason; they're consistently good. There's been enough of these by now that they no longer can be graded on the curve of "good for a superhero movie", but they've remained consistently entertaining enough to not need that handicap. Sometimes they're merely decent (Thor) and sometimes they're absolute masterpieces (Captain America: Winter Soldier). Relative to the pantheon of MCU adventures, Doctor Strange clocks in at a solid B-. I'm looking forward to seeing how they weave this magical element into the greater MCU.