This season Agents of SHIELD has really opened up the Marvel Cinematic Universe by introducing The Inhumans, a race of people who were genetically modified by the Kree millennia ago. Some of them live among us, not knowing they have unique DNA, waiting for it to be triggered by Terrigen mists - which could turn them into superpowered beings or twisted monsters. There's no way to know in advance.
In the comics The Inhumans are ruled by a royal family, and we can assume those are the characters who will show up in Marvel's 2019 movie The Inhumans. Those folks live in a secret city called Attilan, which is futuristic and has been located in the Himalayas, on a breathable patch of the Moon known as the Blue Area, and even over New York City. What's interesting is that Marvel TV has been leading the charge on The Inhumans, which is the first time we've seen the small screen take the reins.
When talking to Kevin Feige at the Avengers: Age of Ultron press junket I asked him about this, and about how much Agents of SHIELD (and the possible new spin-off) would be influencing what comes in the movies.
"It was always the intention that introducing them to the public would be happening quickly, and it would happen in the show," he said.
I asked him how the relationship between TV and movies works on stuff like this. The two are generally independent (ie, the Daredevil show has little to do with Feige and his team), but obviously sometimes they need to work more closely. "There have been discussions between myself and Eric Buckley and Dan Carroll, who is the conduit between Jeph Loeb and the runners, in terms of them saying, ‘We’re thinking of doing this, this and this - does that gibe with what you’re doing in the movies?’ And in some cases, like with the Avengers movies, it’s very close. We have to say, ‘This is happening, so you have to do this.’
"In the case of The Inhumans, they’re blazing new ground. As we get down the road towards that one, we’ll see what the pieces are."
So that means the shows will lay down the foundation for what we'll see in The inhumans?
"Certainly, in terms of those backstories on some of those things. Knowing the comics, you can guess the kind of things you wouldn’t see on a TV show."
So I would assume no Attilan, no Lockjaw (a giant teleporting dog) and, most likely, none of the actual royal family until they get cast for the movies.
The Inhumans have been restructured as the mutants for the Marvel Cinematic Universe - genetically diverse people living among humans - and that's the angle TV will focus on. Until there's a treatment/director for The Inhumans I wouldn't expect to hear much about the royal family at all, or even Attilan, until the studio powers that be decide things like which characters will be in the film and where Attilan will be located. So yes, the TV show is leading the way - but they'll only be able to lead so far.