Gunn's last film Super was a sly deconstruction of comic book storytelling, yet Guardians is a celebration of old school heroism filtered through five eccentric outsiders who form this film's eponymous team. On pure entertainment value, you'd be hard-pressed to find a movie this summer as good as Marvel's latest.
Leading it all is Chris Pratt's Peter Quill, aka Star-Lord, who found himself swiped from Earth by Yondu (Michael Rooker) after the death of his mother and has roamed the spaceways ever since as a mercenary for hire. A mysterious and coveted orb eventually leads him into contact with green-skinned assassin Gamora (Zoe Saldana), wise-cracking raccoon Rocket (Bradley Cooper), talking tree Groot (Vin Diesel) and walking gun show Drax the Destroyer (Dave Bautista). Their adventure takes them into the firing line of Ronan the Accuser (Lee Pace) and intergalactic despot Thanos (Josh Brolin), the villain lurking in the darkness in The Avengers's post-credits sting.
At its core, Guardians is a fleet-footed throwback to the action-adventure movies of yesteryear. Remember when big-screen entertainment wasn't so serious and just really good fun? You can feel everything from Raiders of the Lost Ark to Star Wars and Back to the Future in Guardians's DNA. We're further anchored in the era thanks to Quill's trusty Walkman, which blasts out classic tunes from the Jackson 5, David Bowie and Blue Swede to soundtrack the action.
It's the chemistry between the central quintet that lends the film its heart amid the spectacle, though. Rocket and Groot come as a fully-formed double-act, while Gamora's ties to Ronan put her at odds with Drax, who lost his family thanks to the Kree alien. It's left to Quill to become the unlikely hero, and he does just that by uniting the Guardians in a bid to stop an infinity stone wreaking havoc across an already war-torn galaxy.
As good as the supporting cast is (CGI creations Groot and Rocket have tangible weight and character), it's Pratt who steals the film. The comedy skills honed on Parks and Recreation serve him well here - he's a big screen hero who's part Han Solo, part Marty McFly, with endearing wit and charm that makes him easy to root for.
Further down the expansive cast list there's also stellar work from Doctor Who's Karen Gillan as blue badass Nebula, plus John C Reilly and Peter Serafinowicz as dry-humoured Nova Corps officers. Only Glenn Close (as Nova Prime) gets short shrift in the screen time stakes, while Pace's Ronan doesn't quite match up to the more memorable comic book villains.
Guardians also finds itself largely free from the brand-building baggage that's plagued recent superhero films (Amazing Spider-Man 2 being the biggest culprit). Thanos aside, the film largely operates without reference to the wider Marvel universe - there's no crammed in Captain America cameo or fleeting Nick Fury appearance, instead the focus is on telling a good story, and on these terms Guardians succeeds. Future instalments seem almost assured - let's just hope they match the high standards set by this excellent debut outing.