Most of the time, when you watch a film, you think about the film itself, the narrative, the people in it, the cinematography etc. In this case, you spend half the time wondering what the film-makers were trying to do. It really is worth emphasising what a weirdie this one is. Weird in a bad way.
It is incredibly disjointed. The stars remain completely separated. James Robertson Justice and Charles Hawtrey are in one lot of scenes. Robin Hawdon sans moustache and Yutte Stensgaard are in another lot. RH avec moustache is in a third lot, and Dawn Addams appears in a fourth. There is no overlap between these. The opening twenty minutes with the charisma-free Hawdon & dear old Yutte playing strip poker are so excruciatingly dull that you wonder how many people lasted the course in the days before fast forward buttons. Or maybe pause buttons.
Of course the story is intended to be quirky, and the makers were obviously going for a Barbarella-type vibe. OK, but this one is downright strange. Some of the odd bits include: a completely unmotivated dialogue between James Word and a grumpy lift; the bizarre incident of James Word's moustache, revealed as false in the opening scene; overdubs of Major Bourdon's added dialogue, which sound nothing like James Robertson Justice, but passably like Basil Brush; James Word being fed an aphrodisiac diet of oysters and what appears to be Mackeson Stout; the British secret service employing an American boss and a Scandinavian secretary; the mystery of why Charles Hawtrey's bottom is bitten by one of his own dogs.
Other commentators have unpicked the relationships between the various bits of the film - it looks like the Justice/Hawtrey scenes were shot first, and then the Hawdon/moustache scenes shot to make sense of them, and then the Hawdon/no moustache scenes shot to make sense of them. Stensgaard's lines about what rubbish it all is are clearly a tongue-in-cheek admission of the blindingly obvious. Naturally, the whole thing is a thin excuse for some girlie nudity (and that also is laid on thicker in the scenes shot later, as if they realised that nudity would be the film's only saving grace). The basic idea of topless aliens invading Earth is a very amusing one. But given the cast there really is no excuse for making such an awful picture.
The nadir of the film is the jokey kidnap-and-torture sequence about half way through. Not erotic, just a gigantic lapse of taste, unredeemed by the reappearance of the kidnapped girl towards the end. That is the problem with this film in its most egregious aspect - it is just not likable enough.
