It's understandable that the world of espionage would make great fare for Hollywood. Shrouded in mystery, rife with betrayal and rich with international and interpersonal drama, the globe trotting adventures of super spies has been a cinematic staple for decades. Whatever your theatrical proclivities, the spy genre has something for you. Whether you prefer the tense realism of The Ipcress File or Tinker Tailor Soldier Spy, the campy excess of the Roger Moore era Bond films, the gritty 'shaky cam' realism of the Bourne movies or the stylish flair of The Man From U.N.C.L.E, the spy genre is many things to many viewers.

Here we celebrate a franchise that's thrilled fans of the spy genre since it began life as a network TV show in the '60s and became one of the most successful movie series to feature a non-caped or superpowered protagonist. A franchise that's rich in intrigue, rife with plot twists and turns, studded with spectacular action scenes, gorgeous exotic locations... and lots of running. A franchise that's characterized by increasingly daring and inventive action set pieces and a lead actor who never gets tired of finding inventive new ways to endanger his life in the name of cinematic realism. We're talking, of course, about the Mission: Impossible franchise. With Mission: Impossible -- Fallout just around the corner, many of us have dived back into the original classics to relive their most memorable scenes once more. Our mission, should we choose to accept it (and we do), is to revisit 20 defining moments of the film series that for many is the quintessential spy franchise.

20 SELF DESTRUCTING MESSAGES

The responsible handling of sensitive data is something that all government agencies agonize over. But when it pertains to impossible missions, you know that some extra special measures are in order. One of the classic tropes of the TV show was that Jim Phelps' mission instructions would self destruct five seconds after they had been relayed. It was a fun trope that was fitting for the politically paranoid Cold War era.

The films, however, took this self destruction to a whole new level, with each movie finding new and inventive ways to destroy the mission briefings of Phelps' predecessor Ethan Hunt. Whether they're hidden in phone booths or exploding sunglasses, they're a part of the mythology that every fan looks forward to.

19 JIM PHELPS UNMASKED

Mission Impossible Jim Phelps Mask

While all Mission: Impossible films bring something interesting to the table, Brian DePalma's original remains unmasked in its ability to weave a web of mystery throughout its narrative. Right up until the film's climax we're still not sure who is playing who and to what end.

In the third act, it's revealed that Ethan Hunt's mentor and defacto patriarch Jim Phelps is really the film's big bad as his wife Claire conspires with him in a quiet train carriage. But Phelps sheds his face to reveal a masked Ethan Hunt who knew of the subterfuge all along. Unlike in previous entries, there's no digital trickery at work here, just an outstanding prosthetic by the legendary Rob Bottin.

18 THE KREMLIN BREAK IN

Mission Impossible Kremlin Break In

Infiltration is a huge part of the spy game. Being able to inveigle themselves into well guarded places and steal well guarded secrets is a big part of what makes spies' adventures so appealing. And the Kremlin is surely the embodiment of what springs to mind to Western audiences when it comes to the fortified complexes of secretive regimes.

In Mission: Impossible -- Ghost Protocol, Ethan Hunt and Benji Dunn make their way into this most secure of facilities without the benefit of masks, using a clever device and a whole lot of wits. For all their frenetic action, the Mission: Impossible movies have also proven adept at using silence and tension to Hitchcockian effect, and you'd be hard pressed to find a better example.

17 "YOU'RE NOT DIMITRI?"

Mission Impossible 2 Dimitri Scene

Mission: Impossible 2 is widely regarded as the weakest entry into the canon but it's still not without its merits. It may not be as viscerally satisfying as the best John Woo action films or as tense and clever as the best spy films but it's a whole lot of fun with some cool action moments and some memorable spy moments.

Just take the films prologue, which sees Russian scientist Dr. Nekhorvich liaise with Dimitri (an alias of Ethan Hunt's) on a plane... only to discover that Hunt is in fact the film's antagonist Sean Ambrose in disguise. It's a great spy moment that establishes Ambrose as a credible threat with IMF training and the same skills as Ethan.

16 DAVIAN'S INTERROGATION

Philip Seymour Hoffman was one of the greatest character actors of our time and a colossal loss to us all. While his turn in Mission: Impossible 3 won't be the role he's best remembered for, it shows that a great actor can elevate decent material to greatness. His portrayal of Owen Davian oozes quiet menace and nowhere is this more evident than when he's being interrogated by Ethan Hunt.

Here we see a captive bad guy who, despite his vulnerable condition, is in complete control of the situation. Hoffman's dialogue in this scene would be pedestrian in the hands of a lesser actor but he makes it utterly chilling and compelling.

15 BYE BYE, JACK!

Mission Impossible Jack

Brian DePalma is a master of suspense and has produced some of the best thrillers the genre has to offer. His skills are on display in the first Mission: Impossible which lulls the audience into a false sense of security early on by sweeping the rug from under us. The IMF team in this film is an ensemble cast made of respected Hollywood stars.

Imagine our surprise, then, when the film contrives to kill them off one by one in the first act. The offing of Emilio Estevez' Jack was especially surprising and the affable star was specifically chosen by DePalma for this reason. Audiences assumed that because Estevez was a reasonably big star that he'd be safe... they thought wrong!

14 SUPER SPY V SUPERMAN: DAWN OF MUSTACHE

Mission: Impossible -- Fallout hasn't even been released at the time of writing but it's already had a defining moment in the franchise for some very good and very bad reasons. The image of Tom Cruise's Ethan Hunt squaring off against The Man of Steel himself, Henry Cavill in the trailer understandably had fanboys salivating.

Unfortunately, Cavill's contentious facial hair in the film would interfere with reshoots for Justice League resulting in a rushed digital grooming of the Superman actor's top lip. This would go on to become the subject of months' worth of bitter memes and endless blog posts. Hopefully, when we see these two titans face off in the movie it will all be worth it.

13 ETHAN TAKES FLIGHT

Movies Mission Impossible Rogue Nation Plane Stunt

There are certain things that fans have come to expect from an entry into the Mission: Impossible franchise -- new self destructing message gags, new mask tear reveals, and new ways for Tom Cruise to endanger his life in the name of realism. Cruise (who produced these films as well as starring in them) has always been a stickler for using 35mm over digital and real stunts over digital tomfoolery.

But this stunt represents the pinnacle of Cruise's dedication. That's not Tom Cruise in front of a green screen. It's not a stunt double with Cruise's face digitally superimposed -- that's actual Tom Cruise actually holding onto a plane as it takes off.

12 VIRUS LAB SHOOTOUT

The Mission: Impossible franchise is one of the most beloved and respected action franchises in cinema history. And you can't have an action franchise without gunfights. Lots and lots of gunfights. Say what you will about Mission: Impossible 2, but John Woo can direct gunfights in his sleep and he doesn't disappoint here.

When Ethan breaks into a virus lab to destroy the film's plot device, the deadly Chimera virus, he quickly finds himself surrounded by bad guys and one of the best gunfights in the series ensues. Does Ethan jump through the air firing twin berettas? Of course, Ethan jumps through the air firing twin berettas!

11 PRISON BREAK

Mission Impossible Ghost Protocol Prison Break

Can you believe there was a time when executives at Paramount were worried that Tom Cruise was getting a bit long in the tooth and that the Mission: Impossible series should continue without him? The UK's Evening Standard even suspected that Brad Pitt would be the antagonist of the fourth Mission: Impossible movie... how wrong they turned out to be.

The daring prison break at the start of Mission: Impossible -- Ghost Protocol shows that Cruise and the series have still got it! It's not only a phenomenal action sequence, but the non verbal repartee between Hunt and Simon Pegg's Benji does a great job of establishing their camaraderie. Those same execs learned what we already knew... there's no Mission: Impossible without Tom Cruise!

10 THE LANGLEY BREAK IN

Mission Impossible Langley Scene

Silence can speak volumes. While we all go to the movies wanting lots of bang for our buck, sometimes it's the moments of stillness and quiet that are the most satisfying. So it is with the nerve shreddingly tense Langley break in from the original Mission: Impossible. When Ethan and his ragtag team of disavowed recruits try to steal a top secret NOC list, they conduct an extremely elaborate heist to infiltrate a technologically advanced vault inside CIA headquarters in Langley.

This scene provided the yardstick by which all future infiltration scenes would be measured. Indeed, Mission: Impossible 3 knew that it would never top this gem and so, quite wisely, didn't even try.

9 ETHAN'S TRANSFORMATION

Mission Impossible 3 Davian Mask

There's a reason why we're all so fascinated by the use of masks in the Mission: Impossible series -- they're the perfect metaphor for an espionage drama. You never know who you can trust or what subterfuge may be lurking behind a seemingly friendly and familiar face... but mostly, they just look awesome!

Just take this scene in Mission: Impossible 3 in which Ethan and Ving Rhames' Luther Stickell print, paint and apply a mask to transform Ethan into the film's antagonist Owen Davian. It's a seamless marriage of editing, prosthetics and digital effects that still holds up incredibly well 12 years later.

8 MOTORCYCLE JOUSTING

Mission Impossible 2 Motorcycle Joust

The original Mission: Impossible had its share of bombastic moments, but it was remembered as much for its restraint and intrigue as its action beats. In a way, you have to laud Cruise, producing partner Paula Wagner and director John Woo for throwing out the rule book for the sequel. There was a semblance of a spy narrative, but the espionage was only ever context for the action set pieces.

And they don't come any more excessive than this. Ethan and his nemesis Sean Ambrose charge at each other on motorbikes in a  deadly game of chicken before tumbling off a cliff onto the beach for some mano-a-mano kung fu fighting.

7 UNMASKED AND WINGING IT

Mission Impossible Ghost Protocol Mask Maker Malfunction

With Mission: Impossible -- Ghost Protocol, Brad Bird took great delight in pulling the rug out from under the feet of the characters (and the audience) by subverting the tropes of the franchise. From the payphone message that couldn't quite self destruct on its own to the mask maker that went on the fritz at the worst possible moment.

Without the benefit of masks, Ethan and his team attempt to carry out a trade of diamonds for nuclear launch codes between two parties that could rumble them at any time. It's one of the most intelligently constructed and nail bitingly tense moments in the series. No fancy camera work, no VFX, just an ensemble of great actors doing what they do.

6 DAVIAN'S LIBERATION

Mission Impossible 3 Drone Strike

It's a cinematic convention that never gets old. The bad guy gets captured by the good guy and we should feel elated. But deep down we have a sinking feeling that the antagonist is right where he wants to be. We saw it with The Joker in The Dark Knight, Loki in The Avengers and it's most certainly the case with Davian in Mission: Impossible 3.

Unfazed by his interrogation, Davian knows that it's only a matter of time until he's liberated by his men... a liberation that results in one of the series' definitive action set pieces in which Ethan is thrown into the air by a missile blast then narrowly avoid being decapitated by a drone.

5 FISH TANK ESCAPE

Mission Impossible Fish Tank Escape

By the time Mission: Impossible's first act draws to a close, Ethan Hunt is already been having a very bad day. A seemingly routine operation has left his entire team dead. He is brought in by IMF director Eugene Kittredge and the two meet at a restaurant with a huge ostentatious fish tank.

The meeting does not go well when it's revealed that Hunt is believed to be a double agent who caused the death of his friends. Sensing that things are about to go very awry, Hunt detonates the tank with some exploding chewing gum... and the rest is cinematic history!

4 ESCAPING THE SYNDICATE

There are some fans who believe that the most recent entry, Mission; Impossible -- Rogue Nation is the best entry into the franchise to date, encapsulating everything that's great about the franchise. And looking at this scene it isn't hard to see why. It reminds us just how tough, resourceful and formidable Ethan Hunt is, even without his gadgets, but that's just the tip of the iceberg.

The scene also introduces Rebecca Ferguson's anti-heroine Ilsa Faust who quickly demonstrates that she is at least Hunt's equal both in martial prowess and cunning. While the film (mercifully) refrains from developing a love story between the two, Cruise and Ferguson have a palpable chemistry.

3 SO... MUCH... RUNNING

Mission Impossible 3 Tom Cruise Sprint

There are people who have the looks. There are people who have the talent. There are a lot of people who have the screen presence and the range. But nobody, absolutely nobody in Hollywood can sprint like Tom Cruise. The Mission: Impossible series treats us to some of the best sprinting ever committed to celluloid.

Whether he's running from bullets, explosions, sand storms or the aging process, Tom Cruise does it with aplomb! With Cruise now in his 56th year he shows absolutely no signs of slowing down, and we wouldn't be at all surprised to see him to continue to sprint, leap and vault in increasingly dangerous and inventive surroundings for decades to come.

2 HELICOPTER TUNNEL CRASH

Mission Impossible Helicopter Tunnel Crash Conductor

The Mission: Impossible franchise has become the yardstick by which all other Hollywood action movies are measured in a number of ways. Not least of which is its penchant for heart stopping climactic action set pieces in the third acts. And they set a pretty high bar for themselves from the get go.

Pursuing his nemesis and former mentor Jim Phelps, Ethan finds himself leaping from a moving train to a helicopter within the confines of the (then new) channel tunnel. To prevent Phelps from escaping, he uses a handful of exploding chewing gum to detonate the chopper and the blast of which sends Ethan careening back on to the train. The look on the train conductors face? Priceless!

1 THE BURJ KHALIFA CLIMB

Someday, Tom Cruise is going to look at his call sheet and say, "Hmmm, maybe we should get a stunt guy to do this.". But today is not that day. And tomorrow won't be either! While the series is full of daring and inventive stunts, Mission: Impossible -- Ghost Protocol's Burj Khalifa climb is perhaps the most spectacular.

In order to break into a room in the legendary skyscraper, Ethan must climb in from outside using a less than reliable set of adhesive gloves. The heart stopping tension is amplified by the knowledge that we're actually seeing Cruise crawl up the side of the real life Burj Khalifa... in glorious 70mm IMAX.