'Agents of S.H.I.E.L.D.': A Primer of Joss Whedon's New Fall TV Series

You saw one (or more) of the "Iron Man" movies because of Robert Downey Jr. You saw "The Avengers" because, well, everyone did. You think you are ready for "Marvel's Agents of S.H.I.E.L.D.," the new Marvel-spawned fall TV series premiering Tuesday at 8 p.m. on ABC. You are wrong. You are so not ready. Yet.

Here's what you need to know to watch "Agents of S.H.I.E.L.D.":

The show, in brief: In the wake of "The Avengers," aka the "Battle of New York," buttoned-down Phil Coulson (Clark Gregg) leads a crackerjack crew of specialists in the worldwide fight against comic-book-y crime for the Strategic Homeland Intervention, Enforcement, and Logistics Division, or S.H.I.E.L.D. for short.

Where you've seen Coulson before: "Iron Man," "Iron Man 2," "Thor," "The Avengers," and a couple of shorts, known as Marvel One-Shots, that were made for the Blu-ray releases of "Thor" and "Captain America: The First Avenger." Suffice it to say, the fake Coulson's very real IMDb.com page is longer than the average actor's.

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Where you've seen Coulson, well, die before: "The Avengers." The 2012 monster hit was co-written and directed by the same Joss Whedon who co-wrote and directed the "Agents of S.H.I.E.L.D." pilot, so, yes, the man is well-aware he has some explaining to do. (Spoiler alert: Slash Film purports to have the goods on how Coulson makes it back from his apparent demise. Don't click here if you don't want to know what reportedly goes down in the pilot.)

Meet the "Agents of S.H.I.E.L.D.": 

The Samuel L. Jackson connection, or not: In the Marvel movies that involve S.H.I.E.L.D., Coulson is an underling of Jackson's eye-patch-wearing commander, Nick Fury. Jackson has said he'd like to be a part of the new series: "I'd be, you know, Charlie's voice on 'Charlie's Angels.'" But Whedon hasn't taken Jackson up on his offer — that we know of. A Marvel rep declined to comment on Jackson's "Agents of S.H.I.E.L.D." status, if any.

The superhero factor, or not: While superheroes exist in the "Agents of S.H.I.E.L.D." universe, they don't exist in Coulson's team. At the same time, however, ABC has teased that the pilot concerns Coulson and friends trying to "track down an ordinary man who has gained extraordinary powers."

So, apparently you should watch (or rewatch) "Iron Man 3": There's been much buzz that "Agents of S.H.I.E.L.D." will pick up where this past summer's Downey movie left off, with Extremis, the limb-regrowing power that scientist Aldrich Killian (Guy Pearce) harnessed for ill.

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And apparently you'll want to watch (or rewatch) "The Avengers," too: That way when Cobie Smulders, moonlighting from "How I Met Your Mother" and reviving her "Avengers" turn as S.H.I.E.L.D. Agent Maria Hill, turns up in the pilot, you'll be like, "Hey, cool!" (Marvel, by the by, was mum on whether Smulders/Hill will appear in future episodes. Not unlike Jackson, Smulders, whose sitcom embarked on its final season Monday night, sounds up for more S.H.I.E.L.D. work.)

And apparently you'll want to watch (or find) "Item 47": "Item 47" is one of the aforementioned Marvel One-Shots shorts (this one doesn't feature Coulson), is included in the Blu-ray edition of "The Avengers," and is said to have given Disney CEO Robert Iger the bright idea that S.H.I.E.L.D. should be the basis for a TV series.

We are not kidding: Do not attempt to watch the pilot without studying: Or so says the Raleigh (North Carolina) News & Observer's TV blog, Happiness Is a Warm TV. "If you didn't care enough to see 'The Avengers,' then don't even try to watch this show. You'll HATE it," the blog's Thad Ogburn reports. "And if you're like what I suspect is the majority of us in between — enjoyed 'The Avengers' but not quite ready to do a Marvel comics dissertation — you'll be conflicted about 'Agents of S.H.I.E.L.D.'"

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Then again, don't freak out: You don't have that many years of Marvel lore to catch up on. S.H.I.E.L.D. might have been dreamed up by giants Jack Kirby and Stan Lee in 1965, but "Agents of S.H.I.E.L.D." is a (basically) all-new show with (mostly) all-new characters. Even Coulson himself dates back only to the first "Iron Man" movie — the character is a creation of the movies, aka the Marvel Cinematic Universe, and was not previously in the comics.

Then again, freak out a little: If this is the Marvel Cinematic Universe we're talking about, then you can count on interlocking plots, especially with so many forthcoming plots to interlock: The "Thor" sequel is coming out in November; the "Captain America" follow-up is slated for next summer. Best advice: Keep your screens at a minimum when watching "Agents of S.H.I.E.L.D." You actually may need to pay attention.

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The good news, Hoff edition: Because "Agents of S.H.I.E.L.D." is its own thing, or at least its own thing that doesn't draw much on pre-2008 history, there is no need to dig up the 1998 straight-to-video flick "Nick Fury: Agent of S.H.I.E.L.D.," starring David Hasselhoff as Fury. Then again, once you see the glorious B-movie-vibing trailer, you'll want to dig it up.

The better news, Captain America edition: Per the Hollywood Reporter, Marvel is already prepping another new series, this one based on the love interest in "Captain America: The First Avenger," Agent Peggy Carter, and to be called "Agent Carter." No word on the potential involvement of Hayley Atwell, who played Carter in the film.

Watch a sneak peek clip of the pilot:

Check out "Agents of S.H.I.E.L.D." pictures:

"Marvel's Agents of S.H.I.E.L.D." premieres Tuesday, Sept. 24 at 8 p.m. on ABC.