“Ya see, when a man bleeds, it’s just tissue, but blood from one of you Things won’t obey when it’s attacked. It’ll try and survive… crawl away from a hot needle, say.” It’s the line that launches one of the most nail-bitingly iconic scenes in all Horror Cinema, one that, amid all the gruesome special effects found in John Carpenter’s The Thing, makes effective use of some very humble lab equipment to ratchet up the tension.
With senior biologist Blair (Wilfred Brimley) incarcerated for his own good and physician Copper (Richard Dysart) rendered armless by an earlier attack of the alien organism that stalks the men of Outpost 31 in The Thing, it falls to kick-ass chopper pilot R.J. MacReady (Kurt Russell) to rig a little blood test of his own devising as a means of telling who’s human and who’s Thing. Mac is no kind of medic, so he uses what he can find – some petri dishes diligently labelled with each man’s name and a coil of wire heated by the business end of his flame thrower. The idea is to gather blood samples from each of the surviving men and, well, dip the hot wire in and see what happens.
We the audience don’t really know what to expect, so director Carpenter uses a series of reaction shots of his characters to indicate that the result of Mac’s first attempt to test a sample – a thin, hissing plume of rising smoke when the wire makes contact – is the sign that the man this blood belongs to is human. That’s fine, but we still don’t know just how Thing blood is going to react to the wire. We have a healthy suspicion that eventually one of the samples will definitely react differently, and from the evidence that we’ve been presented with in the run-up to the scene we might well have our own theories as to which man’s sample it will be.
When the moment comes, as we surely know it will, Mac is holding the labelled petri dish containing the alien liquid right under our noses, but the reaction is so brief and violent that it takes eagle-eyed viewers to notice that the hand in which Mac is holding the dish is, somewhat ironically, not human tissue. The effects team had to rig the dish so that a large piece of Thing matter would pop up rapidly to show that it clearly didn’t like the heat from the wire. In order to do this they needed to use a dummy hand in place of Kurt Russell’s own. Watch it again sometime and see if you can spot the manikin fingers clutching the dish.
A further irony, highlighted by the gathering of the blood samples into the row of labelled dishes, is that despite the effects team’s best efforts to make The Thing’s audiences recoil in horror at the sight of all the gory alien transformations, it is those little moments depicting scalpels slicing through thumbs, hypodermic needles sinking into arms and gunshot wounds being sutured that are the bits guaranteed to make a grown man turn his head away from the screen.