Although Brian Appleyard of the Sunday Times described Parry as "wiry and objectionable", television executives and audiences think highly of the former Royal Marine. The BBC has released a DVD of his latest series, a journey down the Amazon, and given it an almost instant, prime time repeat on BBC2.

His visit to the Amazonian Achuar people, explains why his success is ominous. It encapsulates everything that is wrong with the narcissist genre.

Inevitably, Parry sees the Achuar as Rousseauian noble savages, whose holistic lives are threatened by the exploitation of nearby oil reserves. He heads upriver in a small powerboat to meet them, like an environmentally-friendly conquistador looking for a green El Dorado. "I'm soooo lucky to be allowed to come in here," he sighs. "There are no roads, no towns, no real infrastructure other than what the tribal people have traditionally had. As we move slowly upstream I begin to get the sense that we are going somewhere strange and special."

The Achuar territory sounds like a life-affirming, earth-loving paradise, but Parry faces a problem. Thirty seconds' research on Google taught me that the Achuar, like Presbyterian ministers and the old English aristocracy, regard displays of emotion in front of strangers as poor form.

Parry does not seem to know this and spends most of the documentary trying to persuade the Achuar to chill out and accept that BBC journalists are pretty straight guys. Ever since Franz Boas, anthropologists have agreed that they cannot interfere with the cultures they are studying or they will destroy what they are meant to record. No such scruples restrain Parry as he embarks on a mission to be loved.