Comic books: Stay tuned to 'S.H.I.E.L.D.'

"Marvel's Agents of S.H.I.E.L.D." has stopped being a follower in the larger Marvel Universe. Now it's establishing concepts for use in the movies, instead of just sweeping up after them.

If you haven't been following the ABC show, Director Coulson (Clark Gregg) and Agent Skye (Chloe Bennet) have learned that their lives had been saved by an experimental serum derived from a dead, blue alien. Coulson, and some others "infected" by the alien serum, have been forced to scribble strange glyphs on any available surface, glyphs that turned out to be the blueprint of an alien city somewhere on Earth.

Meanwhile, Skye's father, Cal (Kyle MacLachlan), who takes "bipolar" to a truly prodigious level, is in pursuit of Skye (whom he has never met), and is in possession of an alien artifact that allows "the worthy" entrance to the city — an artifact he has given to Whitehall, the head of Hydra. (The artifact kills anyone who touches it who isn't "worthy.") Also working with Whitehall is Grant Ward, a turncoat S.H.I.E.L.D. agent with deadly hand-to-hand combat skills and who, like Skye's father, has a creepy obsession with Skye.

That's a lot to take in, but the midseason finale Dec. 9 managed not only to wrap most of these plot points up in a neat, pink bow, but added new ones. And those plot points promise a leap into the broader Marvel Universe, with substantial impact on movies yet to come — especially one called "The Inhumans," scheduled for 2018.

If you're not a comics fan, settle in for "Inhumans 101."

Back in the 1960s, comics legends Stan Lee and Jack Kirby introduced a band of mysterious superhumans on the run in the pages of "Fantastic Four." They turned out to be the royal family of a hidden race called the Inhumans, who had been chased out of a hidden city in the Himalayas called Attilan after a palace coup.

Each of these characters had a different superpower, and as it turned out, so did everyone in Attilan.The Inhumans were a product of genetic tampering by a blue, alien race known as the Kree back when we were all Neanderthals. Inhumans are generally born normal, but come into their genetic inheritance at adolescence, when they are exposed to the mists emitted by the Terrigen Crystals in a ceremony called Terrigenesis, which activates their Inhuman DNA.

Recently, the mad demigod Thanos of Titan invaded Earth. As Thanos was about to destroy the planet, the Inhumans leader carried out a desperate Hail Mary, in which he blew up a "Terrigen Bomb" that infused our atmosphere with the Terrigen mists, which activated recessive Inhuman genes planetwide.

Instantly, thousands of people all over the world were encased in cocoons, and later emerged as Inhumans, each with a different super-power — and the potential to help protect our planet from Thanos. This has freaked out the regular humans, who have reacted with our standard set of tools: fear, paranoia and violence. Even though these Inhumans were created as our protectors. You might even say they are feared and hated by a world they're sworn to protect.

What's that got to do with "Marvel's Agents of S.H.I.E.L.D."? Well, the Inhumans origin story is pretty much what we've been watching this season:

• The show has already established that the blue aliens whose blood saved Coulson and Skye are the Kree, who gave the Inhumans their powers in the comics.

• S.H.I.E.L.D. and Hydra converged, in the midseason finale, on a hidden city. Hidden cities are big with the Inhumans.