Comic book collectors and Marvel fans beware -- "All-New Captain America," "Superior Iron Man" & "Thor" have been dubbed "smash hits," and for that reason they have flown off of the shelves!

So what now?

"Exciting and ambitious, these Avengers NOW! titles are bringing seismic changes to some of Earth's Mightiest Heroes, reinvigorating and recharging some of the most popular characters in all of fiction," according to Marvel.

"Today, Marvel is pleased to announce that three of these hit titles have completely sold out and will immediately head back to press," the release added.

If you missed out on these "energetic and action-packed comics" the first time, have no fear; like all heroic tales, there's always hope!

You can still nab "ALL-NEW CAPTAIN AMERICA #1," "SUPERIOR IRON MAN #1" and "THOR #2" when they return to comic shops this December.

"Be there when Sam Wilson dons the stars and stripes as the new Sentinel of Liberty, when Tony Stark unleashes Extremis on the city of San Francisco, and when the new Thor tests her mettle against a horde of angry Frost Giants!" Marvel adds.

What did critics have to say about the hyped, three new series?

"A tremendous amount of fun."

- ComicBook.com on All-New Captain America #1

"...these new directions are taking readers to some very fun places" - The AV Club

"Tom Taylor does have a knack for bringing out the worst in some of our greatest heroes...this is a title to keep an eye on." - Comic Vine, on Superior Iron Man #1

"...all I really want out of my Thor comics." - Newsarama, on Thor #2

Marvel fans are also getting psyched for "Avengers: Age of Ultron", which will have Tony Stark (Downey Jr./Iron Man) trying to start a dormant peacekeeping program. But when things go awry, it's up to The Avengers to stop the villainous Ultron from enacting his terrible plans.

In addition to "The Blacklist's" Spader and "The Judge's" Downey Jr., the cast of "Avengers: Age of Ultron" also includes: Chris Evans, Mark Ruffalo, Chris Hemsworth, Aaron Johnson, Scarlett Johansson, Don Cheadle, Elizabeth Olsen, Samuel L. Jackson, Jeremy Renner and Lou Ferrigno, among others.

Marvel's "Avengers: Age of Ultron" hits theaters May 1, 2015.

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