5: Star Wars (1977)
Why It Should've Been Terrible: Confidential memo, dated 1976. "Lucas has lost his mind. His cast includes a dustbin and a giant dog, he's making Alec Guinness do a sword fight without a sword and the cast are openly mocking the dialogue. We're gonna lose millions on this."
How It Became Great Instead: Lucas hadn't lost his mind at all; instead, he'd pinpointed what was in the minds of every kid who ever stepped into a cinema and figured out how to bring it to life.
4: Batman Begins (2005)
Why It Should've Been Terrible: Begins? You're not fooling anybody. We saw Batman And Robin. Batman has already ended.
How It Became Great Instead: By totalling ignoring the Burton/Schumacher years (and, better still, ditching Robin) Christopher Nolan and Christian Bale rebuilt the Bat from the ground up, not only creating the definitive blockbuster trilogy of the modern age but providing a durable template for other franchises with an eye on rebooting.
3: Dr Strangelove (1964)
Why It Should've Been Terrible: "We're all terrified by the prospect of nuclear war. Stanley, cheer us up with a comedy!" "Comedy, eh? I've got just the subject for that."
How It Became Great Instead: Nervous giggles turned into full-blown hysterical guffaws as everybody realised that Kubrick was right. In a situation this crazy, satirical laughter is the only response.
2: Psycho (1960)
Why It Should've Been Terrible: Man turns up at cinema halfway through a screening and is told:
"I'm sorry, Alfred Hitchcock says you can't come in. It'll spoil the surprise."
"What surprise? Films are all the same. It's not like he's going to kill off the main character halfway through or something."
How It Became Great Instead: By ripping up the rulebook, Hitchcock changed movies for ever. Never mind taking a shower, Psycho made us wary about stepping into a cinema.
1: The Lord of the Rings (2001 - 2003)
Why It Should've Been Terrible: Even if "hobbitses" and orcs don't float your boat, the sheer insanity of trying to shoot three films back-to-back will do for this one. Ralph Bakshi couldn't finish the thing, and he had the advantage of not working in live action.
How It Became Great Instead: The greatest gamble in modern cinema paid off, chiefly because Peter Jackson had precisely the right combination of love for the material, hard-earned craft and distance from Hollywood to do it his way.
The rest at the source.