A bemused, confident R-rated semi-spoof of James Bond, "Kingsman: The Secret Service" is adept at tartly twisting convention even as it follows an outline that plays like a 007 origin movie. Writer-director Matthew Vaughn (2011's "X-Men: First Class") and co-writer Jane Goldman (2012's "The Woman in Black") give their picture a winking, absurdist style right from the start, the beginning strains of Dire Straits' purely awesome '80s anthem "Money for Nothing" playing over the studio logos and opening credits. While the film tends to fall into the trap of being a training manual during the long middle act and the silliness doesn't always comfortably mesh with its bleak subject matter, there is an ingenuity and imagination to much of the script that gives it a newfound freshness. Learning that it is based on a comic book by Mark Millar ("Kick-Ass" and "Wanted") and Dave Gibbons ("Watchmen") comes as no surprise.

Seventeen years ago, a widowed mother (Samantha Womack) and her young son, Eggsy (Alex Nikolov), were given a bravery medal when their husband and father perished while on a mission in the Middle East. His partner, special agent Harry Hart (Colin Firth), told them to call the number on the back if ever they were in need. For the wayward, now-grown Eggsy (Taron Egerton), who has just been arrested for jacking a car, that time is now. Recently out another agent, Harry enlists this troubled young man for an unorthodox training program with the top-secret Kingsman organization in hopes of finding someone suitable to take his fallen colleague's place. As Eggsy, the sharp-witted Roxy (Sophie Cookson), and the rest of their competitors are faced with a series of perilous exercises meant to test their aptitude as potential recruits, the agency is faced with their latest adversary: tech tycoon Richmond Valentine (Samuel L. Jackson), who is planning to turn free SIM cards into cataclysmic mind-control weaponry.

"Kingsman: The Secret Service" is like 2006's haphazardly amateurish "Alex Rider: Operation Stormbreaker" if that movie grew up and magically became good. Eggsy is a directionless hooligan when the story picks up with him as a twenty-something man who is still living at home and despising his mom's loutish live-in boyfriend (Geoff Bell), but as far as rebellious protagonists go, the Welsh-born Taron Egerton (in his first major feature film) is imminently watchable and magnetic. He gets a little help from Colin Firth (2014's "Magic in the Moonlight"), excellent in a rare action role as mentor Harry Hart, and Samuel L. Jackson (2014's "Captain America: The Winter Soldier"), perfectly maniacal as squeamish bad guy Valentine, but Egerton by and large carries the film. Able to play tough as well as debonair, his transformation over the course of the film is subtle and even endearing when the training challenges he faces require both selfless sacrifices he is willing to make and a cold, no-nonsense brutality that goes against his nature. As rival/cohort Roxy, newcomer Sophie Cookson shows definite promise, but is underutilized as nothing becomes of the friendship-and-maybe-more set up between her and Eggsy. As Arthur, the aging head of Kingsman, Michael Caine (2014's "Interstellar") gets even less to do—he is off screen for so long it is easy to forget he is in the movie until he reappears—while Sofia Boutella is memorably lethal as Valentine's cutthroat henchwoman, Gazelle, using her prosthetic racing blades to slice people in half.

In general concept, the plot sounds like more of the same, a familiar adventure about an unlikely hero who discovers an ability for greatness he never knew he had. It was the premise for not only the aforementioned "Alex Rider," but also 2000's "Charlie's Angels," 2003's "Agent Cody Banks," and just about every superhero and sports movie in existence. It is a formula that is nothing new, and yet there is a ballsy inspiration to this film that sets it apart even as its most grim elements threaten to hinder it. A bravura single shot showing Eggsy running down steep railings and jumping from level to level of a multi-story apartment building is either a case of Egerton being a brilliant stuntman or effects trickery that would be best to not know about. Later set-pieces involving a flooded room, a group skydive where one of the jumpers is wearing a faulty parachute, and an unflinching killing spree in the middle of a fundamentalist church are breathless assaults to the senses. When it comes to this latter scene and Valentine's central scheme to wipe out most of the world's population, the film's giddy, joking aloofness to mass casualties threatens to become crass (especially when a veritable fireworks display of exploding heads is scored to KC and the Sunshine Band's disco hit "Give It Up"). Sure, the movie as a whole isn't meant to be taken seriously, but Vaughn is so in tune with Eggsy's personal growth that it feels disingenuous to abruptly segue from sincerity to grisly farce.

In spite of a few questionable tonal shifts and a spare misstep here and there—a subplot involving the disappearances of real-life celebrities and dignitaries is missing the expected payoff—"Kingsman: The Secret Service" makes a name for itself because of its buoyant, frequently bawdy sense of fun. As controversial as one sexual tryst at the very end might be, it is not to be taken seriously as it smartly turns the spirit of James Bond on its head. Indeed, were Bond to not have to worry about attracting a family-friendly PG-13 audience, he and his movies would probably be as no-hold-barred as this one. If a new franchise has just been born, it is very likely to ripen with age.