It's a medical fact that psoriasis - the debilitating skin complaint - can be exacerbated by stress ...so it's no surprise to see writer Dan Dark resembling a "human pizza".

He's mentally plagued by a tortured childhood, the bitter knowledge his career has stalled and the fact his marriage is careering towards the rocks.

Covered in supporating, cracked lesions, he escapes from his torment by imagining a parallel world where he is the pulp fiction Singing Detective.

His noirish nemesis is Binney (Northam), a slimy lothario with connections to the mob who just happens to share the name and looks of his mother's lover.

Dark flits into this nether world where his cravings are satisfied (The Singing Detective has got Binney's number) everytime the pain becomes too much.

Director Keith Gordon uses the late Dennis Potter's unfilmed screenplay, which the writer had already adapted to be relocated to America.

Here Dark, as portrayed by Downey Jr, is far younger than the British version played by Michael Gambon in the seminal BBC show.

Fans of the TV series will be pleased to know there's still the scene where Dark has to imagine life's most boring things - baby seals, fortune cookie sayings - to fend off arousal when a nurse smears his body with cream.

And the seguing of scenes into ironic song-and-dance routines has also been carried over but don't seem so powerful in the music's American Fifties setting as opposed to post-war Britain.

Downey Jr delivers a technically impressive performance but his character - dripping bile and hate "like he's fallen into a sewer" - isn't one of the most sympathetic.

Modern references to the likes of Mick Jagger and Donald and Ivana Trump also jar slightly, seemingly out of place.

Rather cold and soulless, the caustic wit of Potter's original is absent and the whole affair is something to be admired rather than liked.

Tim Evans