UPDATE 10/29/2014 10:24 AM PT: Video removed at the request of Disney.
At Tuesday's announcement-packed Marvel Studios event in Hollywood, Marvel Studios President Kevin Feige announced the upcoming two-part "Avengers: Infinity War," with Part 1 scheduled for May 4, 2018; Part 2 slotted for May 3, 2019.
Marvel Studios has teased an "Infinity Gauntlet"-type storyline for years now, with "Infinity Stones" -- known as "Infinity Gems" in the comic books -- first popping up in the form of the Tesseract in 2011's "Captain America: The First Avenger" and 2012's original "Avengers" movie, followed by the Aether in last year's "Thor: The Dark World." The main plot of this summer's "Guardians of the Galaxy" also revolved around an Infinity Stone.
At the presentation on Tuesday, Feige unveiled a teaser for "Infinity War" composed primarily of footage and narration from past films revolving around the Infinity Stones -- and culminating in a new shot of Thanos (Josh Brolin) wearing a Stone-filled Infinity Gauntlet. That teaser has made its way online -- albeit in a low-quality version surreptitiously recorded by someone in the audience -- at least until Disney and Marvel have it yanked off of YouTube.