Channel 4 has a reputation for sensationalism, and television a liking for in-jokes. On the face of it, Cast Offs, a drama serial that shows disabled people not only left to fend for themselves without sufficient supplies on a deserted island but naked on its shores, is a reality-show parody designed to create a tabloid flurry. Its inspiration might have been Nigel Kneale’s 1968 drama The Year of the Sex Olympics, in which reality television was foreseen and fore-skewered.

But, to judge by its first episode, Cast Offs is something else: both a brilliantly observed comedy drama and a breakthrough in television’s depiction of disabled people.

It is not that television ignores them, although they are almost certainly under-represented (outside it, they make up between 12 and 16 per cent of the working-age population). Critics claim they have too often been confined to the roles of either victims or “supercrips” who, through heroism, triumph. Hard-line sociologists distinguish between impairment (physical) and disability (socio-cultural) and condemn even telethons for equating disability with a tragedy that needs to be undone by charity.

In fact, television has always shown disabled people undefined by their wheelchair (the wheelchair is television’s shorthand for the disabled, as it is for the sign-writer).

On BBC News we see Frank Gardner, the security correspondent, in his. CBeebies employs Cerrie Burnell as a presenter despite a minority of parents’ complaints that her missing lower right arm, the result of a birth defect, “frightened” toddlers. In the past, in drama, one recalls Raymond Burr’s Robert Ironside, Sandy Richardson crippled by a car crash in Crossroads, even Commander Shore in Gerry Anderson’s Stingray (although his electric wheelchair’s main purpose was to save the puppeteers the embarrassment of walking him jerkily across Marineville).

Channel 4 has, in recent years, included disabled characters in Shameless, Skins and Hollyoaks. The difference is that these days disabled people are played by actors who are disabled: the deaf actress Marlee Matlin, who took a recurring part in The West Wing, would be an example from America.

So far, however, when the humour has got black, it has usually been left to able-bodied actors such as Peter Kay, as Brian Potter in Phoenix Nights, and Matt Lucas, as the faker Andy Pipkin in Little Britain, to fill the wheelchair. Even Timmy, the hydrocephalous sufferer on South Park, is voiced by the perfectly fit Trey Parker.

But in Cast Offs the actors are as disabled as their characters and, consequently, licensed to deliver a script that not only faces up to disability, but jokes about it (“I’m a man in a chair, boom boom; But I have pubic hair, boom boom”), sometimes cruelly. The castaways describe themselves as monkeys: See No Evil (Tom, who is blind), Hear No Evil (Gabriella, deaf) and Face No Evil (April, who has cherubism).

Cast Offs may be the first television drama about disability that never asks for our sympathy.

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