The Accusation: Not for the first (or last) time, producer Roger Corman took one look at the box-office and made his own cheap 'n' cheerful variation. In this case, changing one Great White for a shoal of killer fish allowed him to remake Jaws without a single shark.
The Spark Of Originality: As scripted by John Sayles and directed by Joe Dante, this is a gleefully exuberant mash-up of B-movie gore and sly satire.
The Accusation: Surely Pixar's most offbeat premise - elderly refugee flees via balloon-powered house - is an original? Not so, according to the student filmmakers of French short Above Then Beyond , which has the same premise.
The Spark Of Originality: The French film ends with the house flying into the sunset... which is only the end of Act 1 in Up . Talking dogs and rare birds are still to come.
The Fast And The Furious (2001)
The Accusation: Swap the cars for surfboards, and the homo-erotic bromance between Vin Diesel and Paul Walker in a beat-for-beat reprise of 1990s' action classic Point Break .
The Spark Of Originality: Enough juice in the tank to build a franchise that's still going strong - Fast Six is currently filming.
The Last House On The Left (1972)
The Accusation: Believe it or not, there were audience members for Wes Craven's gruelling horror show who recognised where they'd seen the story before - Ingmar Bergman's bleak Medieval drama, The Virgin Spring .
The Spark Of Originality: The unrelenting anguish of the victims' ordeal, a call-out to the real-life horrors of Vietnam Craven saw on the nightly news.
The Untouchables (1987)
The Accusation: Brian De Palma was denied the budget to film his big 'train rescue' set-piece, so he improvised by copying the iconic Odessa Steps sequence from Battleship Potemkin , even down to the pram.
The Spark Of Originality: The integration of the falling baby into a traditional cop movie shootout is an inspired cranking up of tension.
The Accusation: Vincenzo Natali's ingenious one-set sci-fi thriller borrowed the economic shooting techniques of old-school TV, specifically a 1961 episode of The Twilight Zone called Five Characters In Search Of An Exit .
The Spark Of Originality: The clever redressing of the same set in order to convey the impression of characters moving through multiple rooms within the cube.
The Accusation: It's nigh on impossible to tell a sci-fi or horror story that hasn't already been done by The Twilight Zone . Even so, Poltergeist 's riff on 1962 episode Little Girl Lost (about a youngster pulled into another dimension from her suburban home) is pretty blatant.
The Spark Of Originality: The use of the television set as the means of transportation, influencing a whole generation of J-Horror directors.
Raiders Of The Lost Ark (1981)
The Accusation: Yes, yes, the entire film is a riff on 1930s film serials… but those in the know swear that Indiana Jones' appearance is a near-exact replica of Charlton Heston's costume in 1954 adventure Secret Of The Incas . Judge for yourself.
The Spark Of Originality: The original lacks the iconic mixture of Old Testament spectacle and hissable Nazi villainy that makes Raiders so enduring.
The Incredibles (2004)
The Accusation: The specifics of the Parr family's powers - strength, elasticity, speed, invisibility and flames - were so reminiscent of Marvel's Fantastic Four that the makers of the latter's film adaptation had to tweak their script.
The Spark Of Originality: The 'nuclear family' satire of the Parrs trying to lead normal lives after a ban on superheroes, even though that element was lifted from Watchmen.
Taxi Driver (1976)
The Accusation: Stick Travis Bickle on a horse instead of in a taxi cab, and the character - loner, war veteran, racist and compelled to search for a young girl kidnapped by villains - is a dead ringer for Ethan Edwards in The Searchers .
The Spark Of Originality: The added psychological realism achieved through Paul Schrader's confessional screenplay and Robert De Niro's committed performance.