It's something of an irony that Billy T James' big breakthrough - which is to say his first star turn on television - had him cast as a poncy English twit by the name of Dexter Fitzgibbons.
We may fondly remember Billy as the Maori with that infectious giggle, making us laugh at dreadfully corny one-liners on Te News.
But the inescapable inference to be drawn from his TV career is that he had to be made into a pakeha before he could be allowed to be a Maori.
That was the tenor of the times, of course. As several of the interviewees in this serviceable documentary recall, New Zealand in the 1970s wasn't used to seeing brown faces on TV, even on the "light-ent" shows that were our staple fare.
Billy, a born mimic, made a great fist of Fitzgibbons, the MC for the nostalgic variety show Radio Times, but to me he always looked slightly ill-at-ease, aching to bust out and cut loose.
Still, the part proved his ticket into the upper reaches of showbusiness and, for what now seems like a cruelly short time, he was a superstar.
Much has been made of how Billy's Maori caricatures made "us laugh at ourselves", but it was a good deal more complicated than that. He took a lot of stick from radicalised Maori at the time and it is at least arguable that he pandered to crude stereotypes without deflating them - or the rednecks who subscribed to them - one little bit.
Only his astonishing charm and peerless skill allowed him to get away with a shtick that Howard Morrison, for example, never managed - but he didn't win over all of the people all of the time.
It's a theme touched on in this film and dealt with more substantially in Billy, the biopic that screens on TV One on Sunday (lumpy and sometimes stilted as that film is, I emerged with a greater understanding of the man than I gained from Te Movie).
Director Ian Mune, who cast Billy as the show-stealing Tainuia Kid in Came A Hot Friday and producer Tom Parkinson, the man behind Radio Times and Billy T Live at either end of Billy's career, plainly know their subject. But the film suffers from the lack of a central organising idea that is the essence of all good films, especially good documentaries.
Certainly it covers the ground, starting with the early years in Leamington, near Cambridge (where Maori were not exactly thick on the ground in 1949), and ending with a sensitive treatment of the conflict over his body - a matter sickeningly sensationalised by news media at the time. It also usefully reminds us of his astonishing musicianship.
Anyone expecting a big-screen Billy T James Show should beware: there is an adequate, though scarcely generous, selection of clips, but much of the film is the talking heads of former collaborators remembering him, and striking insights are few.
A notable exception comes from Laurie Dee, Billy's straight man for so many years, who remarks at one point that "we thought we knew him, but we didn't". Perhaps we never will, but this film takes us close.
*Join us for a live online chat with director Ian Mune here from midday.
Director: Ian Mune
Running time: 89 mins
Rating: PG (Drug references)
Verdict: More blah-blah than ha-ha