"Force of Life" was "Force of Evil." I was going to make it a much more malevolent force but, in fact, I reconsidered and then in talks with Gerry and things I decided it was much better that this creature had no sort of actual human malevolence, that its actions should be what it was; without good, without evil,simply doing its thing.
I think Force of Life embodied that notion that, here were people in an environment that could be hostile, indeed that was invariably hostile, encountering things about which they had not the faintest idea. Here, they encountered an emblem of the life that they had left behind: chrysalids that turn into caterpillars and caterpillars that turn into butterflies...these are part of the natural rhythms of our lives. Well, it seemed to me to be perfectly reasonable to suppose that this process was universal and that it could happen in the most extraordinary, interesting and completely mind boggling way without understanding what made it work. And that's what Force of Life was about.
I wanted to get away from the notion of the kind of good and evil. You know, the nasty, mad alien and the cowering Earthlings. That's a valid form of story and, you know, we'd seen it ad nauseum in Star Trek and I think too much of it came in later on into Space. In "Force of Life" to many forms of life out in space intelligent Earth life means bugger-all. It means as much to a wisp of gas up in space and here I had the kind of mindless evolutionary imperative at work. We picked up a random force going through a kind of chrysalis stage in space. Its decision to latch itself onto Zoref was purely arbitrary. He happened to be in the right place at the right time and, of course, there was something about him which attracted the creature. But it had not got any kind of intelligence in the sense we understand intelligence, it had an imperative, a kind of instinctive thing driving it. Of course, these things have to be visualized in terms of science fiction for the screen so the way I found it was to turn him into a heat-junkie, he was just like an addict. The thing inside him would need a fix every so often and we had him going through these spasms where he'd draw heat out of any object, including coffee, including people, including anything thus finally...again I applied to the tail end. I applied the technique of the first story where you look at the situation and see what's the inescapable sort of logic and try to build on it. This force had been ripping its way as part of its evolutionary imperative through the base and the effects it has on human rituals are very simple. I think David did it very well.
We wanted to make it different in the sense that it didn't have a a kind of conscious heavy...it had a force affecting people. The force had its own reasons for doing what it did and they were perfectly understandable in terms of itself. But it had a kind of unthinking, devastating effect on the people. I thought the use of camera angles, pace and effects were quite stunning. David did some wonderful sequences of Zoref going through those corridors and the lights were fading into him.
Someone, I think, forced me to put in the notion that it was a star in the making. I think that this was a foolish notion, because it was better to say that we simply didn't know what it was. If you want to draw a comparison, it's the caterpillar and the butterfly, but in some impossibly difficult and imponderable circumstances. It was one of those situations where not knowing the answer was where the drama lay. Knowing would have killed the drama.
I felt that the performances and the direction were superb. David Tomblin got a tremendous sense of pace with Ian McShane striding through those corridors, which are usually the most boring of shots but somehow David could invest them with tremendous energy and drama. David could communicate that sense of urgency...you would actually get off from watching somebody walking down the corridor.
Given the nature of the relentless need for story in these things, it was often very difficult to develop aspects of character. There are a huge number of balancing acts and trade-offs that one had to incorporate into these stories: anything that walks in from outer space or outside Moonbase Alpha has to be explained whereas, in contemporary drama, anything that walks in off the street doesn't need any explanation; the need to keep the story moving very fast because people are assumed to have the attention span of a gnat and can't really comprehend anything in the way of difficulty in terms of drama and ideas; and also the distribution of roles between the leading actors and those brought in for the episode. These things didn't always work, but I think that this one perhaps worked better than most in terms of the directorial flare that David brought to it. I was very pleased with Force of Life.
Comments by Johnny Byrne, abridged from an interview with Tim Mallett and Glenn Pearce and a 1982 interview with Carsten Andresen.