[SPOILER WARNING: This article contains mild spoilers in the description of the film's basic plot.]

To folks who pay close attention to these things, the narrative surrounding "Guardians of the Galaxy" these past few months has received more attention than the movie itself. A small fleet of think pieces, blog posts and old-fashioned in-person conversations have reached a common conclusion: "It's Marvel's riskiest film yet!" This very website ran a column in February titled, "Could 'Guardians of the Galaxy' Snap Marvel's Epic Cinematic Winning Streak?" -- exploring the legitimate possibility that Marvel Studios' risk may not result in reward.

And there were plenty of valid reasons to think that: The star of the film, Chris Pratt, is far from a household name (though you could say the same about Chris Hemsworth before "Thor" debuted in 2011). The co-writer and director, James Gunn, is a cult favorite but hadn't helmed a film of this scale (sort of similar to Joss Whedon's position before "The Avengers" became the third-highest grossing film of all time in 2012). The characters are obscure even to most comic book fans (not unlike "Blade," which kickstarted the Marvel movie renaissance back in 1998).

It remains to be seen if "Guardians of the Galaxy" will achieve the lofty financial heights of its fellow recent Marvel Studios films -- though, given tracking, strong marketing and the already-announced sequel, box office success certainly feels inevitable. But creatively? In a movie where many things could have gone very wrong, Gunn and company absolutely nail it. "Guardians" is brisk, endearing and comedic in a way that goes beyond the standard witty banter and one-liners, transporting the film into "genuinely funny" territory.

Much has already been discussed about the eclectic cast of characters that comprise the "Guardians" main cast, a team that was first pulled together at Marvel Comics in 2008 (a much narrower comics-to-screen transition than most Marvel films) by writers Dan Abnett and Andy Laning. Other than Pratt's lead role as Star-Lord, all four characters are visibly non-human to varying degrees -- including, of course, a gun-toting, talking raccoon and a friendly tree monster -- but they don't feel alien. It sounds cliche to say, but it really is true: Rocket (voiced by Bradley Cooper) really does prove to be more human than many action movie characters, and Groot (voiced and motion-captured by Vin Diesel) is able to express an impressive range of emotions despite being limited to three words (and despite being a friendly tree monster).

While it is a little disappointing that a movie with such an eclectic cast still has a handsome white male as its lead, it's hard to take issue with Pratt's actual performance. Best known for his supporting role on NBC's "Parks and Recreation," Pratt brings his usual likeable energy and alters it just slightly to fit the scope of things. And "slightly" is important -- a big part of the fun is watching Chris Pratt deliver the type of performance that you'd hire Chris Pratt for, albeit in epic space battles with the fate of the galaxy at stake. It's clear throughout the movie, but cemented during an unexpected scene -- no spoilers here -- involving the film's antagonist, Ronan the Accuser (Lee Pace), right at the climax. (You'll know it when you see it.)

Zoe Saldana, playing Gamora, is obviously a genre movie veteran at this point, between two "Star Trek" films, "Avatar" and "The Losers," the latter based on a Vertigo comic book series. She equips herself well into the Marvel world -- though hints of a romance between her and Star-Lord feel a little unnecessary and obvious, it's one of the most active and ass-kicking roles yet for a female protagonist in a Marvel movie. Dave Bautisita rounds out the main cast as Drax the Destroyer, a former WWE Champion in the largest and most high-profile acting role of his career. Though he has the most understated part of the five, the movie plays that to its advantage, resulting in several laughs (along with the fight scenes you'd expect from him).

The actual plot of "Guardians" is pretty basic -- mysterious powerful object that the bad guys want, and the good guys want to keep away from the bad guys (plus morally dubious smuggler Yondu, played by Michael Rooker, somewhere in the middle). Yet it's definitely more about the journey than the destination -- all of that is an excuse for fun action scenes with an enjoyable cast of characters, and for at least the introductory film in a series, that's probably enough. Ronan is not the most dynamic villain in Marvel movie history, but it's an impressive visual and his vulnerability in scenes with Thanos (Josh Brolin) adds at least the hint of another layer.

Oh yeah -- Thanos is in this movie, too. Though it's the most standalone film yet in the Marvel canon -- not being set on Earth helps that -- there are still teases of what's to come, along with developments in the ongoing "Infinity Stones" story, as seen in "Thor: The Dark World" and elsewhere. There is a post-credits scene, but it wasn't included in advance screenings -- looking at the calendar, an "Avengers: Age of Ultron" tease seems likely.

"Guardians" could have been a tough film to watch. It's full of weird-looking aliens, and jumps from planet to planet without spending more than a few minutes (at the very start of the movie) on Earth. That all sounds like it asks a lot of the audience, but Gunn and co-writer Nicole Perlman keep things warm and relatable. An undeniably huge part of that is the soundtrack -- full of '70s rock hits like "Come and Get Your Love," "O-o-h Child" and "Cherry Bomb," which actually have a story-based reason to be there. That contrast is deliberate and clear -- exploring strange new worlds while hearing a song as immediately familiar as "Stuck in the Middle with You" is pretty much an apt metaphor for the whole film (and makes it worth the small fortune it likely took to get the rights to all of those tunes).

This is not the last risky film on Marvel's schedule. "Ant-Man" -- another lesser-known property which has experienced some very public shifts in both director and cast -- will be released next summer. Yet if anything should earn Kevin Feige and the Marvel Studios crew the benefit of the doubt, it's the high degree of difficulty pulled off in "Guardians of the Galaxy." It's a surprisingly heartfelt and frequently hilarious summer blockbuster that has Rocket Raccoon, Glenn Close and John C. Reilly in it. The mere fact that it exists is novel. That likely millions and millions of people will watch and enjoy something with its roots in a relatively obscure corner of the Marvel Universe? Well, that's pretty cool, too.

"Guardians of the Galaxy" opens in theaters Friday, Aug. 1, with early showings on Thursday night.