The film has bothered to go and shoot on real African locations and this immediately gives it a much greater conviction in contrast to the usual studio backlot jungle sets and back-projected scenery of abovementioned B-movie staples. The dinosaur effects are highly convincing – the film makes the most sophisticated use yet of the old person-in-the-rubber suit effects. The film was made prior to Jurassic Park (1993) and the advent of CGI and, although not always completely convincing, contained some of the most convincing dinosaur effects put on screen up to that point. The scenes with the dying male nuzzling its mate or of the baby indulging in water sports and playing with monkeys have an astonishing tenderness. Probably the dinosaurs have been anthropomorphized towards mammalian behaviour far more so than ever was the case and for their brain size, and the child substitute theme is overdone, but the emotional conviction and tenderness with which they are mimed rides over such rough spots. For Disney, while never leaving their family image, it’s a significantly more adult film than usual – even addressing the use of birth control pills, and having Sean Young stand up to make a strong pro-choice “My body, my right,” statement at one point.

The film believe it or not is based upon fact, namely an expedition conducted in 1980 by University of Chicago biochemist Roy P. Mackal into the Congo in search of legend the natives called ‘mokele-mbembe’ (a name the film is happy to appropriate), which Mackal strongly believed was a brontosaurus. The film’s principal point of departure with truth being that Mackal never found his ‘mokele-mbembe’.