Never let it be said that there's a lack of imagination in Hollywood. For every great film that comes out there's someone happy to create a sequel, then another and, when the possibilities for sequels have run out, a prequel. Not to mention those that, rather than spin the yarn further forward or back are happy to simply rework a film.

Some sequels actually better the original film, though it is very rare. There are things to do that make a sequel a worthy investment both of studio money and audience attention. Sequels need to stay connected to the original story line (which is why the Indiana Jones trilogy, sorry - quadology, won't be mentioned) and to take it and the characters further. It's also important to maintain the same qualities that made the first film worthwhile.

The main characters need to be present too, there's nothing worse than a sequel where only one cast member has taken the paycheck to comeback or only a couple of minor player appear - has anybody seen American Pie: Band Camp?

Widely hailed as one of the greatest sequels, Godfather 2 ticks all the boxes needed. The characters are the same as in the first, the story is a direct link to the end of the first and takes both the characters and the plot further. It's also of the same quality of performance and writing as the first film.

You've also got to know when to stop, of course, or you'll end up with a Godfather 3. While the characters remain as close as allowed by deaths in the previous installments, some key cast members bowed out and the story was overly complicated and lacking in quality in comparison to the first two films. Just as its predecessor was hailed as a great sequel, Godfather 3 was mauled as a terrible sequel.

Knowing when to stop means that we won't be getting a fourth installment in the Bourne films, though Bourne Supremacy was a superb sequel, but not knowing when to stop meant that Mission Impossible 3 exists and Mission Impossible IV is in pre-production. It's also the reason behind 7 Police Academy films, each more mirthless than the first insipid offering.

So, when the idea of improving a film with a follow up isn't appealing what do you do? Write an entirely new and genre defining film? Of course not, all you need to do is make a prequel. A film that takes place before the events of the first film.

Except that, no prequel has ever really added anything to the original film and, by definition, are pointless. Look at the Star Wars trilogy briefly. They weren't included in the sequel section as they were conceived as a trilogy and made close enough back-to-back. At the start of the first film everything that the audience needs to know is explained in an iconic an oft parodied scroll of text. Three great films, job done.

Not if you're George Lucas and have become bored of touching up your old films with digital effects. Why not come up with the weakest possible of story ideas, set it before your original trilogy, go over the top with computer effects, forget all about characters and good writing and create cinema's mast annoying character in Ja Ja Binks and call it a trilogy of prequels. Not just one, but three equally damning and poor prequels that each served to ruin the good work done by the original.

There's now a ridiculous number of prequels: The Scorpion King, Dumb and Dumberer, Carlito's Way; Rise To Power, Butch and Sundance; The Early Days. Not one of them has a redeeming feature and are all filled with awkward attempts to cue up the events of the original film and thus prove themselves essential. What's next; Tom Hanks in Recruiting Private Ryan?

When those hacks referred to as writers have drained the soul out of films with sequels and prequels there's still no need to write something new. Not when they can simply re-create an old film. While it may not seem like a creditable idea, there are some good examples of re-makes but you must bring something new to the original.

For examples of some worthwhile re-makes let us look to two of the all time greats; Robert De Niro and Al Pacino. Both have stared separately in re-makes (Cape Fear and Scarface both updated the originals and added stellar acting from both performances) and starred together in one. Heat was a re-make of Michael Mann's L.A Takedown which he'd failed to find funding for and simplified into a made-for-television movie. Following Mann's success with The Last of the Mohicans he found no problem getting funding, backing and big names to star in his films and re-made L.A Takedown, bigger, better and bolder than the original and managed to get two of the world's greatest actors in the same film.

Of course, if you've got absolutely nothing to add to the film in terms of plot or development and merely want to throw in a handful of current stars, don't bother. If you do you'll end up The Pink Panther remake that haunted cinema screens in 2006 or an entirely pointless remodel of The Italian Job that decided to make the classic British movie into a pointless vehicle for Mark Wahlberg and Jason Statham. Also proving a surprising failure - given the calibre of its cast and creative team - was the remake of The Ladykillers from the Coen brothers and starring Tom Hanks.

Taking the re-make idea to an overly literal translation, Gus Van Sant decided to re-make Psycho shot for shot in an effort entirely without meaning or merit that demonstrated how to spend and estimated 20 million dollars pointlessly. Some remakes are so terrible that something good comes as a result. Take Swept Away, Guy Ritchie's dire re-make of the 1974 Italian film Swept Away by an Unusual Destiny in the Blue Sea of August. Panned everywhere the film had a positive impact in the movie world as it's star, Madonna, swore she'd never act again as a result. Now, that, is a result.