The greatest thing about the Marvel Cinematic Universe is that just when you think you've got it figured out, they'll throw a curveball your way, in the likes of something like the charmingly goofy "Ant-Man," the outer space adventurousness of "Guardians of the Galaxy" or, most recently, the psychedelic prog-rock album cover mind-bendiness of "Doctor Strange."

"Doctor Strange" (out on Blu-ray on February 28) sees the gifted neurosurgeon Doctor Stephen Strange (played, winningly, by Benedict Cumberbatch) have his hands crushed in an auto accident, leading him to seek more alternative therapy on the other side of the world. That's where he gets involved in cosmic impossibilities, battling giant monsters, dabbling in time travel, and generally teeing himself up to be the Sorcerer Supreme of the Marvel Cinematic Universe. It's so, so good.

Earlier today, I sat down with director Scott Derrickson, who spoke to me about Dan Harmon's contributions to the final movie, why Cumberbatch also played the film's otherworldly baddie, and whether or not the mystical stronghold changed its password after one of its members went bad.

It goes without saying that there is a very heavy SPOILER WARNING issued for the following, but since everyone and their magical cat already saw this movie, I'm less concerned.

Moviefone: Just wanted to start off with a serious question: Did they have to change the Wi-Fi password at Kamar-Taj after Mordo left and went bad?

Scott Derrickson: [Laughs] No, I think they would keep that Wi-Fi password.

So, if Mordo was in the neighborhood, he's got his laptop, no problem.

Well, as you know, accessing Wi-Fi doesn't mean accessing any systems within Kamar-Taj.

Oh, that's true. So, this is such a unique take on the Marvel Universe. Was there ever any push-and-pull in terms of just how far you could push things?

No, I think everybody was in agreement that we needed to push it really far. My starting mantra, to use that word, was that every set piece in this movie should be the weirdest set piece in any other movie. So I wanted every set piece to be unique and be weirder than anything you'd see in any other movie. We were just pushing our imaginations as far as we possibly could to come up with the most outrageous concepts, and using the comic books as inspiration for some of those concepts -- obviously -- and then trying to go past them. There was never anything but enthusiasm on Marvel's part for that approach.
Talking about set pieces, I wanted to talk about that final set piece, which is so striking. It almost felt like a commentary on the endings of most superhero films. Was that conscious?

Yeah, it was. The common criticism I had seen was, "Every Marvel movie ends in a big fight, where there's a portal opening to some other dimension and they destroy a city to close the portal." So I thought, "OK, what if we have the un-destruction of a city and, instead of closing the portal, we go into it and go to the other side." So that was the idea. Before we'd even written a script I said, "I want this final battle to be people fighting forward in time while the world is un-destroyed in reverse time around them." It was just a concept and an impossible one, one that had never been done. But I just said, "Well, let's write it and figure out how to do it. And that's what we did."

And when Strange gets to the other side, he essentially annoys the villain into defeat. It felt very much like a "Star Trek" original series gag, and I know Kevin Feige is a big "Trek" fan. Was that something that you referenced?
No, we never referenced specifically "Star Trek." I remember exactly where I was standing when that idea first came to me. Because we were struggling with the ending, and I just threw out this rough pitch of it.

[Writer] Jon Spaihts was there and [executive producer] Stephen Broussard was there, and we started the batting the idea round. We were about to leave. We'd been working for hours and right as we were about to leave, I threw that idea out there -- while we were standing there -- and started throwing it around and by the end of that session, we had the concept.

Jon went away and wrote it. And out of all the things from the first draft of the screenplay that Jon wrote, that's the section of the script that remained untouched. It came in so good that we said, "This is the end of the movie. We're keeping it."

Another aspect of that final sequence is Cumberbatch playing Dormammu. How did that come about?

It was actually Benedict's idea to start with. He was asking who was going to do it, and I didn't know because we hadn't cast anybody yet. I think he was just asking in passing. Then he came back to me and said, "What do you think about me doing it?" And I said, "Well, why would you want to do it?" He said, "Well, I think I'd do a good job," which was a great answer. So I told him I'd think about it and went away and thought about it and I thought: "Nobody could understand that character better than Benedict because he knows the movie inside and out." And the fact that he was game to do it and willing to do it was great.

So I became convinced, not just because he's such an amazing actor, but because Dormammu is the inverse of Strange at that point -- he's the ultimate egomaniac, when Strange is becoming more self-sacrificial. I went to Kevin and said, "Benedict is willing to do this, I think we should let him do it." And he said, "Why?" And Kevin just agreed [with my reasoning] so we did it.
The movie came out and was obviously a huge, huge hit. But were you nervous at all? And what was your reaction to the reaction?

The last screening I did for the film was at USC, my alma mater. And Kevin Feige is also a USC graduate. So we agreed to do a screening and it was on the Friday night of its release, so the reviews had already come in. It was over 90 percent on Rotten Tomatoes and the box office projections were in the [$80 million range]. So I knew it was a huge success.

I was standing outside the theater at USC, waiting alone, and here comes Kevin walking up, and he's so approachable and down-to-earth. He's wearing his ball cap and his sweatshirt and his tennis shoes and drinking a Starbucks. He said, "Well, how do you feel?" I said, "I feel relieved." He kind of smiled. I said, "Kevin, someday somebody's going to make a bad Marvel movie. But it ain't gonna be me." He laughed really hard at that.

What was your main takeaway from the Marvel process? A lot of filmmakers talk about what it's like going in there and trusting the machine.

It's not a machine at all. I think the biggest takeaway is that Marvel movies and the quality of Marvel movies are the result of a handful of creative people who are producers, but they're artists and film-lovers first. They approach the creative process without any ego at all. They're not egotistical, they don't need to be right, they don't need to have things done their way -- and you go in with all of your talent and all of your skillset as a director and all of your vision, they hire you for that vision. They want you to make your movie. They are there to help you and help find the best possible ideas. So, if your ego is checked at the door, everybody finds the best idea together. Everybody wants somebody to have the best idea, all the time. There's very little arguing or conflict. It's mostly just hearing ideas and shooting ideas back. The best idea always wins.

For the most part, this movie was born of my imagination. I came in with a very hard take, based on the comics, and I was always pushing the envelope of what was possible to do. And they got behind it. I've never felt more supported as a filmmaker.
Is it hard for you to help develop this character and then watch him go off into other movies? He's going to be in "Thor: Ragnarok" and "Avengers: Infinity War." Do you call the other filmmakers and check in on him?

No! I'm excited to see what the other filmmakers do with him! I get asked this question a lot and it would probably make me a little uneasy, but I love these filmmakers so much. It's like, "What's Taika [Waititi] going to do with Doctor Strange? I can't wait to see that!" He's an extraordinary filmmaker.

I only know the story of "Infinity War" because I ran into (co-director) Joe Russo outside the bathroom at Marvel, and we got to talking, and he pitched me the movie while we were standing there. So I know the story, but I don't know how Strange fits into it and I don't want to know. I want to go to those movies and be surprised by where the character shows up.

It was reported that Dan Harmon was brought in. And just as a fan of his I was wondering what he brought to the movie.

Well, Dan is a proper genius. He really is. Joel McHale is my best friend, and my family and his family have a BBQ together every weekend, that's no exaggeration. And my kids have seen every episode of "Community," which means that I have seen every episode of "Community" multiple times. The more I watch that show, the more I think he's a certifiable genius. He really is.

Meeting him in person -- he's odd and quirky -- but what he did was, he came in, saw a cut of the movie, and had a really striking analysis. Because he hadn't read any of the scripts and didn't know the Doctor Strange mythology and I'm not sure how much of a comic book fan he was. But he saw the movie, loved it, and had some breakdown things that were very helpful. That alone was probably his biggest contribution. Then he went off and wrote different things. There are some jokes that might have stayed in there, but for the most part, the scenes were a little too out in Dan Harmon-land, even for "Doctor Strange." But I really love the guy and I really think he made a significant contribution in the process. He was the voice we needed to hear at the time, and I will always be thankful and watch anything he does. He's a brilliant dude.

I know nothing has been announced, but is this a character you'd like to return somewhere in the Marvel Universe?

I hope so. I love the character so much, and I also love the incredible possibilities that the movie opens up for future stories. So all the timing would have to line up and all of that kind of stuff. But I hope so.

"Doctor Strange" hits Digital HD and Disney Movies Anywhere on February 14 and Blu-ray on February 28.