In the US adult gamers have been able to buy and play Manhunt 2 since last year. But in the UK the game is not available for sale and developers Rockstar are not even legally able to share the game with journalists.

Copies of the game can be bought on eBay from US sellers. But in order to play it I had to visit the developer's London offices in person and be shown the US copy of the title.

The BBFC says its position is clear. When it was first banned in June last year, David Cooke, director of the BBFC, said: "Manhunt 2 is distinguishable from recent high-end video games by its unremitting bleakness and callousness of tone.

"There is sustained and cumulative casual sadism in the way in which these killings are committed, and encouraged, in the game."

Developer Rockstar is no stranger to controversy - it faced criticism over last year's title Bully, mainly from a press which mis-understood the game and assumed the player took on the role of a bully. In actual fact, the player's role was to challenge the bullies.

But its highly successful Grand Theft Auto series has come in for regular criticism that the titles glorify crime, especially violence.

Rockstar says its position is equally transparent: It says it makes games that are "well within the bounds established by other 18+ games".

Before playing the game I sat through two of the most violent films of recent years - Saw and its sequel.

Both films have 18 certificates and are blood-laden, gore-fests which feature torture, mutilation and strong violence throughout.

Manhunt 2 is a similarly violent and blood-infused experience. The player takes on the role of Danny, who makes his escape from a mental institution leaving behind a trail of murdered guards and inmates.

The method of his killing is particularly gruesome - the player can stab, kick, beat, axe and even suffocate characters in the game.

There is also the option to make the deaths more spectacular - the longer a certain button is held, the more violent the ensuing death.

Death and murder is one of the principal elements of the game, along with basic puzzles.

After about two hours playing Manhunt 2, it is impossible to argue with the BBFC's assessment that the game is unremittingly bleak and callous.

But the violence is stylised - and not particularly real. The deaths play out as mini-scenes reminiscent of action in the current crop of horror movies that are doing so well at the box office, such as Hostel, Cabin Fever and the two titles I had watched.

And the amount of killing in the game is no greater than in any number of titles that have been released in the last 12 months - from Call of Duty 4 to Bioshock.

The game is currently in limbo. After the BBFC was told to issue the title with a certificate by its own Video Appeals Committee, the organisation sought and won a judicial review which forces the VAC to look again at the game.

The BBFC successful argued that the VAC had been guilty of "a very serious misdirection of law" on the question of harm.

The BBFC has been the UK's "censor" for more than 90 years but in the last 20 years it has asked for fewer and fewer cuts in films, reflecting both a modernised certification system and a more liberal attitude.

Last year it asked for cuts in just five films, compared with almost 60 in 1989. No figures are available for games but Manhunt 2 is certainly the most contested title in UK history.

As games become ever more photo-real and as developers start tackling ever more adult themes the BBFC could find itself at the centre of more disputes if it continues to be the body which classifies games in the UK.

There is a growing body of opinion calling for pan-European game classifications to replace national systems.

There is currently a voluntary system, called PEGI, which sits alongside BBFC ratings in the UK.

Dr Tanya Byron, who is conducting a review of video games and their impact on children, is believed to favour PEGI replacing the BBFC.

One game developer told BBC News that he believed the Manhunt 2 controversy was "the BBFC trying to prove it has teeth in an attempt to avoid being pushed out of the way in favour of PEGI".

Rockstar says it is committed to seeing Manhunt 2 released in the UK and one staff member said he was "quietly confident" the VAC would rule in its favour.

Critics of the classification system point out that the VAC is a panel chosen by the BBFC and it is unclear when the committee will meet to decide the game's fate. A spokeswoman for the BBFC said no date was in the diary.

She said: "Classification is not a science; it's a judgement based on guidelines.

"It went too far. There are concerns about the whole tone of the game and what it may or may not do to people who play the game.

"Our judgement is a line we have drawn at this game," said the spokeswoman.

"If the VAC do not find in our favour, then that line has to move," she added.

Gamers and the game industry are waiting to see what happens to that line.