Eraserhead (1977)
The Unlikely Leading Man: David Lynch regular Jack Nance, who met the director in the seventies and was eventually cast in Lynch's first film as Henry Spencer, the much-bothered and beleaguered lead.
How He Got The Part: Lynch isn't exactly known for conforming to convention, and that's certainly true with his feature debut.
Not least with the casting of Nance, who's just odd-looking enough to pull off the lead role - not least with that impressively bouffant hair.
Bob & Carol & Ted & Alice (1969)
The Unlikely Leading Man: Branded "an angsty leading man who caught the spirit of his times", Elliot Gould is the unconventional romantic lead in this comedy drama.
The plot follows a group of four friends whose romantic feelings are, shall we say, complicated.
How He Got The Part: Gould's comedy timing is spot on, and he's great as uptight Ted, who would rather bottle his feelings than serve them in a champagne glass.
The 40-Year-Old Virgin (2005)
The Unlikely Leading Man: The Daily Show player Steve Carell, who jumped to leading man status with this Judd Apatow comedy after small(er) roles in Bruce Almighty and Anchorman .
How He Got The Part: The whole point of the film is that he's not exactly George Clooney (can you imagine Clooney as a 40-year-old virgin?), which means Carell was perfect for it.
Also, he wrote the part for himself (alongside Apatow).
School Of Rock (2003)
The Unlikely Leading Man: Tenacious D frontman Jack Black, who puts his musical skills to good use as a likeable (fake) teacher in this comedy.
How He Got The Part: Mike White wrote the role specifically for Black, a buddy who used to be his neighbour.
It's not hard to see why - Black's perfect as the lovable loser. Cheeky, spirited and really funny. He needs to do more roles like this.
Annie Hall (1977)
The Unlikely Leading Man: Woody Allen, who's the romantic lead in his own romantic drama.
Allen plays Alvy, a comedian who's besotted with Annie (Diane Keaton) but whose constant over-analysis threatens to destroy their fledgling relationship.
How He Got The Part: Allen wrote the role for himself, and it's a good thing he did, because Alvy is basically a magnified version of Allen.
Walk The Line (2005)
The Unlikely Leading Man: Joaquin Phoenix, who plays singer Johnny Cash in this hard-hitting biopic.
He landed an Oscar nomination, which sort of tells you how good he is.
How He Got The Part: Phoenix was able to transform himself so utterly into Johnny Cash that co-star Reese Witherspoon admits she "had to step it up a notch" opposite him, which is probably why he got the role.
The Terminator (1894)
The Unlikely Leading Man: Former body builder Arnold Schwarzenegger, who wanted to play the deadly Terminator in James Cameron's future sci-fi despite having a funny accent and relatively little acting experience.
Schwarzenegger ended up turning the T-800 into a cultural icon, not least thanks to his (intentionally?) robotic line-readings.
How He Got The Part : Quite simply, he met with Cameron and made such an impression that Cameron ended up unable to imagine anybody else as the T-800.
Platoon (1986)
The Unlikely Leading Man: Having played a string of villains, Willem Dafoe decided he needed to shake things up in order to avoid typecasting.
The result was playing 'goodie' Sergeant Elias in Oliver Stone's Vietnam flick.
How He Got The Part: Stone had seen Dafoe in To Live & Die In LA and was interested in turning that villainous persona into something more benevolent.
It was arguably a turning point in Dafoe's career.
The Notebook (2004)
The Unlikely Leading Man: One-time Mouse House presenter Ryan Gosling, a geeky little kid who grew up into a geeky adolescent, taking on small roles in Remember The Titans and Murder By Numbers.
The Notebook turned him into a rom-com dreamboy and, of course, since then he's become THE leading man everybody wants in their movie.
How He Got The Part: Director Nick Cassavetes wanted somebody "not handsome" to play Noah, which is why he plumped for Gosling.
We imagine he didn't say that to Gosling's "not handsome" face.
The Odd Couple (1968)
The Unlikely Leading Man: Practical joker Walter Matthau, who once circulated a rumour that his middle name was 'Foghorn' and that his original surname was Matuschanskyayasky.
He stars as grumpy bachelor Oscar in this classic comedy, who takes in Jimmy Stewart's suicide divorcee and quickly discovers that co-habitation isn't going to be easy.
How He Got The Part: Matthau played the role on Broadway before it was turned into a film - and he managed to hang onto the part despite Jackie Gleason originally looking to play Oscar on-screen.
Which was lucky for Matthau, because it set him up as an unconventional movie lead and birthed his first collaboration with Stewart.
