The Hangover (2009)
The Bros: Phil Wenneck (Bradley Cooper), Stu Price (Ed Helms) and Alan (Zach Galifianakis).
The Shenanigans: Our trio take part in the ultimate male-bonding experience: the stag do (multiplied by Vegas). Phil and Stu were already friends, but they get to know Alan over the course of a hectic couple of days hunting for the AWOL groom.
Just Friends? So it would seem, though Alan develops a bit of an infatuation with alpha wolf Phil.
Butch Cassidy and the Sundance Kid (1969)
The Bros: Butch Cassidy (Paul Newman) and The Sundance Kid (Robert Redford)
The Shenanigans: The nineteenth-century outlaws get up to all sorts, including a train robbery that results in a cross-country pursuit, before attempting to start a new life together in Bolivia.
Just Friends? They're both quite close to Sundance's ladyfriend Etta, with Butch taking her out for the iconic bike ride.
Sherlock Holmes (2009)
The Bros: Sherlock Holmes (Robert Downey Jr) and Dr. Watson (Jude Law)
The Shenanigans: Guy Ritchie's reboot saw the eponymous sleuth and his purely-platonic cohort on a mission to take down the enigmatic (and supposedly dead) Lord Blackwood.
Just Friends? They both have their own love interests, although their blokey bickering has more than a bit of the 'old married couple' about it.
I Love You, Man (2009)
The Bros: Peter Klaven (Paul Rudd) and Sidney Fife (Jason Segel)
The Shenanigans: Peter's getting married soon, but he lacks a buddy worthy of the Best Man role, so he goes on a series of 'just friends' dates to find someone up for the challenge, but it's Sidney who ends up catching his eye.
The pair bond in a typically manly manner, with guitar jamming sessions, rock concerts and generally just hanging out. It's no wonder Peter's fiancee feels a little left out.
Just Friends? If Peter wasn't already engaged, who knows what might have been?
The King's Speech (2010)
The Bros: Prince Albert/King George VI (Colin Firth) and Lionel Logue (Geoffrey Rush)
The Shenanigans: This bromance crosses the class divide, as the reluctant monarch employs the Aussie therapist to help him overcome his stammer.
That Britain is on the brink of war, and Bertie's abdicating brother is swanning around with Mrs Simpson, adds an extra frisson of tension to the fledgling relationship. A killer radio speech finally seals their lifelong friendship.
Just Friends? Yes, this is a professional acquaintance that blossoms into a stiff-upper-lipped camaraderie.
Robin Hood (1973)
The Bros: Robin Hood (Brian Bedford) and Little John (Phil Harris)
The Shenanigans: Two spiritual brothers, once again bonded by their outlaw status. Their day-to-day activities include liberating Nottingham from Prince John, winning archery competitions, and robbing from the rich, naturally.
Just Friends? Well, we know they both have a tendency for dressing up as women, which they seem to do pretty convincingly.
Starsky & Hutch (2004)
The Bros: David Starsky (Ben Stiller) and Ken Hutchinson (Owen Wilson)
The Shenanigans: How many great bromances have begun with a pair of reluctant cops being partnered against their wills? Starsky and Hutch are forced to team up to tackle Vince Vaughn's drug kingpin, and the swathe of crime he's cutting through California.
Just Friends? Hutch is a bit too successful with the ladies to think about seeking solace with his partner.
Top Gun (1986)
The Bros: Maverick (Tom Cruise) and Iceman (Val Kilmer)
The Shenanigans: It's a case of mutual distrust and loathing for the majority of the movie, though that iciness eventually thaws into respect. When they're not flying F-14s at the Top Gun training school, they're most likely to be playing beach volleyball, or hanging around in underpants/towels.
Just Friends? With all those steely glances (and the homoerotic volleyball matches), this has had tongues wagging for years...
Star Trek (2009)
The Bros: Kirk (Chris Pine) and Spock (Zachary Quinto)
The Shenanigans: A cross-species bromance here, as Kirk and half-Vulcan Spock meet at the Starfleet training academy. Despite locking horns over the Kobayashi Maru simulation, the pair eventually come together to take on Eric Bana's Captain Nero.
Just Friends? Platonic, with Spock burning Kirk when it's revealed that the former is involved with Uhura.
The Odd Couple (1968)
The Bros: Felix Ungar (Jack Lemmon) and Oscar Madison (Walter Matthau)
The Shenanigans: Almost the yardstick for bromantic relationships, Lemmon and Matthau went on to have an enduring screen relationship.
Here, Oscar takes in his recently-dumped buddy Felix, but they quickly get fed up with each other, and their contradictory ways. Thankfully they resolve their living situation (and their friendship) before the movie's out.
Just Friends? Well they do say opposites attract...