IT has taken 26 years for seminal radio series, TV show and novel The Hitchhiker's Guide To The Galaxy to make it to the big screen thanks to its creator Douglas Adams' notorious perfectionism and his untimely death, aged 49, three years ago.

How then does first-time director Garth Jennings' film manage to look so rushed? It reduces Adams' chaotic comedy of the galactic journey of Arthur Dent, sole survivor of a blown-up Earth, that actually made science fiction and computers funny for a confusing 100 minutes.

Such streamlining sacrifices, bafflingly for what is a comedy, most of the humour.

What made Hitchhiker's great was Adams' Pythonesque love of language and the absurd. The impatience of this film has little time for interchange so replaces it with a kind of visual shorthand which it hopes will appease longtime fans of the material.

For example Ford Prefect is seen carrying a towel at all times but there is no reason given for this. Only fans of the series will know why, others will be flummoxed.

Also when Dent and friends arrive on the painfully poetic Vogons' planet they are repeatedly hit in the face by trowels that appear out of the sand.

Adams was at pains to explain that the trowels appeared when someone had an idea anathema to the blindly bureaucratic Vogons but here it appears as reasonless slapstick.

A great proportion of the memorable lines and jokes have been pushed aside in the same brutal manner that earth must make way for an inter-galactic highway at the start of Adams' story.

Perhaps the filmmakers decided that the plotless chaos of Adams' work would not translate to a modern audience. In this vein they have made the quest for life, the universe and anything the main story thread which is in direct contrast to the original work.

There the whole point was that such a big question was irrelevant and Dent's journey through the galaxy was led by no more than a desire to get home and have a decent cup of tea again.

Unfortunately the film's relentless pace and merely-hinted-at plot confuses just as much. Dent (Office star Martin Freeman), Ford Prefect (rapper Mos Def) and Zaphod Beeblebrox (Sam Rockwell) jump from planet to planet with barely a word to explain why.

The book, The Hitchhiker's Guide, which was such a big part of the TV series owing to excellent graphics and Peter Jones' sardonic narration, is used only sparingly. Stephen Fry is the new narrator and as usual sounds rather too pleased with how clever he is.

Bill Bailey's voice pops up to articulate the last thoughts of a sperm whale plunging to earth and is quite funny but this classic scene has once again been heavily edited for the film.

Perhaps the television series' most famous sequence of all giant computer Deep Thought's answer to the meaning of life has been abusively cut.

Voicing the computer, Helen Mirren sounds very bored and the lead up to the classic pay-off her answer is a rather unsatisfying "42" is unforgivably rushed and it all falls flat. It is akin to dying on stage doing Monty Python's parrot sketch.

Freeman has that everyman quality needed for Dent but he is far more weasely and annoying than Simon Jones, the original Dent in the television series. Jones does turn in a very funny scene as a holographic warning system.

Mos Def's appearance has caused some umbrage among Hitchhiker afficionados and though it is a strange choice he does have an odd, quiet charisma and one need only see his performance in this year's The Woodsman to see he is an actor of great ability.

There has also been some disquiet about Rockwell, mostly at the Pez-dispenser like appearance of his character's second head, but I quite warmed to his arrogance.

Once again stealing the show is Bill Nighy, who plays planet designer Slartibartfast.

He is his usual decorous self but makes the most of his small part.

Most of the money has gone on some undeniably excellent special effects the planet scapes look fantastic and Jim Henson's Vogon puppets are superb. Such visual thrills can't compensate for the plot which is light years away from the ingenuity of Adam's work.

The film is dedicated to Adams and the last scene has the infinite improbability drive transforming the spaceship into an image of Adam's face but the film remains an unsatisfactory legacy to the great man.