From a western viewpoint, the Papua New Guineans' interpretations of seeing 'whiteman' for the first time - with his strange clothes and gadgets, eg. aeroplane and gramophone - can initially seem comical. I think that this is for two reasons:
1) The subtitles do not attempt to soften the New Guineans' direct way of talking. On seeing and hearing the plane, one woman says 'We were pi**ing and sh**ing ourselves'; on seeing a westerner wearing shorts, 'We thought he must have a very long penis wrapped around his waist under that lap-lap (loin cloth).'
2) Their conclusions that the white people were spirits of their ancestors returning from the dead, that the aeroplane was a huge bird, and the gramophone a 'box of ghosts', are of course totally logical, but nevertheless as humorously endearing, as is a child's simplistic logic. (Mentioning this second point can sound condescending and culturally superior – an issue discussed at length in the American Anthropological Association paper "Laughing at First Contact", Visual Anthropology Review, AnthroSource, March 2006.)
The Leahy brothers are not portrayed as particularly shrewd and exploitative, and state frankly that they were there in search of gold, Eldorado-style. It's quite believable that they shot and killed to protect themselves from attack, if indeed their other-worldly status dissolved so soon, and their steel spades and axes so quickly became objects of desire. In further support of the Leahy's 'defensive' killings is the notion that belligerence and inter-tribal aggression is evidently an entrenched part of the society. (See the second film of the trilogy, 'Joe Leahy's Neighbours'.)
Regarding the Australians' influence upon 'currency', the programme suggests that notions of wealth and status were already in existence: their manifestation in terms of land and pig tenure simply had a new dimension added: kina pearl shells – to inevitably one day become paper money of course, which itself, ironically, is also the kina, PNG's national currency.
It would have been interesting if, during their interviews with the two surviving Leahy brothers, Connolly and Anderson had probed them about their activities with girls. The girls themselves – now elderly women in 1983 – talk frankly and casually about how they were encouraged by their own husbands to lay with Masta Mick and his brothers in exchange for shells. They overcame their initial fear, gained some trust of the white men, were impregnated, and today appear proud of their mixed-race offspring. We learn about one, Joe Leahy, in the third installment of the trilogy, 'Black Harvest'. Whether or not you would term this sexual trading 'exploitation' depends on your point of you. In any case Joe Leahy is (arguably) portrayed as a man of relative dignity who who tries hard to straddle, even to bridge, the abyss between his parents' cultures, prioritising his own business success whilst also trying and advance the Gariga tribe's wealth through coffee farming. Again, you may or may not deem his actions exploitative, depending on your reaction to 'Black Harvest'.
The 'it's-come-from-the-sky!' reactions of the New Guinean people in First Contact reminded me of the well-known South African film The Gods Must Be Crazy, a fictional comedy in which a Kalahari bushman finds a glass bottle which has dropped from a plane. In that film tragedy underlies the humour, tragedy which is fully revealed in the DVD's accompanying 'making of' documentary. Meanwhile, although First Contact shows 'whiteman's' sudden arrival jolting the very foundations of the Highland communities, shattering their hitherto self-contained world, and catapulting them into a process of rapid familiarization with the West, the film makers do not inherently suggest any negative repercussions triggered by the Leahy brothers' coming, even if there in fact were.
To stumble upon this powerful documentary on You Tube was an enlightening experience - though unfortunately it no longer seems available there. The book upon which the film is based - also called First Contact, also by Connolly and Anderson - may be even more detailed and fascinating. Whether or not it is, as another reviewer has commented, such instances of 'first contact' with isolated communities of people caught on audio-visual record must be few and far between - even more so today than in 1930.