What on earth do you need explained? I mean, it all pretty much stands to reason. Clearly, if you’re driving along and run into some guy who just ran into the roadway because he’s freaking out because he jammed a length of rusty iron pipe into his thigh, and then end up having sex with your girlfriend by the ditch he lands in, you’re gonna end up with a hunk of metal embedded in your skull. Goes without saying, really.
What also goes without saying is that, once that happens, your body is going to start sprouting various lumps of scrap metal, and before you know it, a breakfast with the missus is going to be ruined by your new genital-drill popping up through the table. And as a lesson to the ladies, you might think your boyfriend’s new equipment is pretty alluring, but following through on that attraction is a bad idea. This part of the film was really just a public service announcement–Japan at the time was having a regular epidemic of coital genital-drill-related fatalities. The coroners were getting sick of it.
The problem with that isn’t so much the physical bloody mess, or the emotional trauma of having to simultaneously come to terms with now being a walking scrap-heap, but that the original metal fetishist you ran over is going to resurrect through the bathtub your dead girlfriend is in. In a post genital-drill mishap, people are stressed, and tend to forget that fact, and so that portion of the film serves to remind them–again, a PSA.
Now, there’s a nested theme here–while various kinds of metal transformations are going to take place when you get chunks of iron jammed into you, if you use a rusty piece, you’ve got this whole corrosion thing going on. So kids, be careful to use a fresh and stainless iron pipe before gashing your leg open and ramming it inside.
If you’ve got a rusted metal fetishist and a non-rusted inadvertent-iron man in the same quarters, a fight is going to ensue. And that fight’s inevitably going to move into your city’s very worst abandoned industrial district. This really is the most troublesome part of the film, seeming frankly a bit racist, which I guess one could tie to the xenophobic attitude Japan often gets blamed for–but it suggests that if two iron men, one being rusted and the other not, are to ever cohabitate, they will do so in such a way that they make a mutual pact to destroy the world. They’ll only do that once they fuse into an anthropomorphic tank-like vehicle, but still.
It’s really a quite straightforward film.
And if you think that’s odd, TM’s, have a look-see at “Tetsuo 2: Body Hammer” some time, which is a similarly cautionary tale about the long-run dangers of teaching your children to transform into guns.