The film's narrators, Frank Finlay and Vanessa Redgrave, provide commentary that combines the knowledge of human biologists and anatomical experts.

In March 1969 Battersby met with Nat Cohen at Anglo-Amalgamated who agreed to provide the other half of finance on that day.

[6] Geesin later said: It was an attempt... to put a deeply socio-human documentary about the human body into cinemas, using some then-pioneering micro-camera work: coursing along the various tubes and all that.

Similarly the internal photography, though technically superb when it shows, for instance, urine passing into the bladder in geyser-like gusts, amounts to little more than a flow of colourful images, with not much more significance than the arty shots of a grotesquely magnified toe-nail being cut.

In fact, the film is most successul when it is most straightforwardly informative, as in the final sequence of the birth of a baby, or the tour round a warehouse containing the thirty tons of food which the average Western man eats in fifty years, though the attempt to contrast this with the average Asian's diet is ruined by the coy whimsicality of the commentary.

The gap between intention ('I want my films to assist people to get an insight into their lives and to understand the society they live in, so they are better able to change it') and achievement is most obvious in those sequences in which Roy Battersby cuts together unrelated shots in an attempt to give them a single meaning ... this procedure simply creates a montage of unrelated or arbitrarily related images.