Ricky Gervais graduates to Hollywood leading man in Ghost Town, David Koepp’s supernatural comedy about a curmudgeon who discovers that he can see dead people on the streets of Manhattan.

Unfortunately, the award-winning star of The Office and Extras simply doesn’t have the charisma to carry an entire film, falling back on his usual repertoire of comic tics and mumbled asides.

Screenwriters Koepp and John Kamps rely on Gervais’s unsympathetic misanthrope for the majority of the laughs, a risk that doesn’t pay off, resulting in uncomfortable longueurs when every punchline falls flat.

Saturday Night Live regular Kristen Wiig is a blessed relief as a litigation-shy surgeon who tries to cover up an unfortunate turn of events on the operating table.

“You died... a little bit,” she eventually confesses to Gervais’ dumbfounded patient. “Everybody dies,” she adds soothingly.

“Yeah, usually at the end of their life," he replies,” “and only the once.”

There’s every chance audiences could die of boredom well before the end of Koepp’s film and its emotionally-manipulative, mawkish denouement which recalls Scrooge’s transformation in A Christmas Carol.

During a routine colonoscopy, middle-aged dentist Bertram Pincus (Gervais) reacts badly to the anaesthetic. His heart stops beating but thankfully staff revive him on the operating table.

Bertram wakes to discover he can now see and hear the spirits of the recently departed, all of whom are stuck in limbo.

Tormented by one particular soul, Frank Herlihy (Greg Kinnear), Bertram agrees to speak to the dead man’s widow Gwen (Tia Leoni) in the hope this will facilitate Frank’s transition to the other side.

Instead, Bertram unexpectedly feels an emotional connection to Gwen, and he wrestles with a growing attraction.

Ghost Town could have been a quirky and charming romantic comedy with a different leading man. Regrettably, with Gervais on board, the project becomes a limp one-man show, with hardly any room for Kinnear or Leoni to breathe life into their underwritten protagonists.

Computer-generated special effects are used sparingly to allow ghosts to walk through solid objects, but occasionally extras forget that they aren’t supposed to be able to see or hear the spirits.

In a bar scene, for example, patrons clearly turn around when they hear a ghost argument.

Sexual chemistry between Gervais and Leoni is completely inert, rendering Bertram’s romantic overtures pathetic.

He’s certainly no credible match for Gwen’s human rights lawyer fiancee, played with suavity and charm by Billy Campbell.

When Frank attempts to sabotage the fledgling relationship by feeding Bertram bogus details about a dream that only Gwen would know, the dentist is apoplectic. “You lied, why did you do that?” he rages.

“Because you’re a heartless son of a bitch who only cares about himself – and she’s already had one of those.”

We wholeheartedly agree.