I’m a sucker for a good zombie film, and for some reason there seems to be no shortage of them recently. I Am Legend is the latest in the crop, and it’s the zombies that let the film down unfortunately, since the director chose to have them portrayed by digital animation when real flesh would have been so much more expressive.

Still, some good choices were made in other respects. The abandoned and overgrown New York the story takes place in is amazing to behold, with deer and lion in the streets, and subtly effective sound design hinting at other fauna. But is it any more effective than what was done on a much lower budget in 28 Days Later? The answer has to be no, which is a shame though there’s still plenty to like about this film.

What really got me thinking was a clever, if perhaps slightly over-seasoned use of an interesting device when Will Smith’s character meets up with a mother and son who’ve also survived the apocalypse (brief recap: it was Emma Thompson’s fault). Now, both the adults are used to being the alpha characters in their stories, with a subordinate kid or dog that does what it’s told. They’re not used to having to treat anyone as an equal, because for years now in Will’s life there hasn’t been an anyone. Instead, he’s lived a prolonged teenage existence where he collects weapons, fantasises about the mannequins he has arranged in a DVD store, and plays Bob Marley loud as he drives round the city. Having met someone else again, he and the woman are going to have to work at adjusting to this new reality where power and gender are once again part of the equation.

There are a few ways this could be handled. And most of them would be either dialogue-heavy or overly symbolic. What I Am Legend does instead is use a device I call the One Step Remove…let me tell you about the first time I rumbled this gambit.

In the wonderful Broken Flowers, Bill Murray is searching for an ex who may be the mother of his son. At the end of the film, he has an encounter with a teenager who reckons Murray may be his father, and the story is all the more interesting for it: the boy fulfils all the criteria that Murray ascribes to his son, but is not him. He is one step removed: the boy, and maybe Murray, have made an attribution error that saves us from who knows what schmaltz may have ensued in the hands of a less talented director than Jim Jarmusch.

Another form of One Step Remove is when a character imparts information from another source than what we can see and hear onscreen. It could be a will, or a psychic reading. At any rate, information that changes the state of the person hearing it, probably creating a turning point in the story.

It’s also what’s happened on a message board debate I’ve been following, about whether or not to ban one member for alleged misogyny. Some of the posters implied that the continued presence of the accused would result in them leaving. One of the board moderators noted that this could be an inappropriate form of leverage to use. Later, a poster popped up to declare that several of the board’s members had indeed stopped posting: by getting him to announce it, they had effectively done exactly what the moderator had raised concerns about, but did so through another poster. Not contributing to a debate is one thing: telling others that you’re not contributing is another, a piece of information in its own right, and one particularly suited to the environment of a message board where the participants know each other through their screen interactions. That’s a binary position: they’re either there or not. By getting a third party to declare their status as non-participants, they found a third position to take, one in which their very silence has meaning.

So, the One Step Remove - essentially a way of dealing with a writing challenge indirectly rather than head-on - is an interesting and nuanced strategy when used well. Which is what they do with it in I Am Legend. When Will Smith and the female survivor meet up, all the potential dynamics between them are dealt with by the inventive device of the woman’s son watching Shrek, and Shrek and Donkey articulate the different strata of powerplay that exists between the two characters, both at times having their voices doubled up by Will Smith, who has watched the Shrek DVD plenty of times since he holed up in his post-apocalyptic hidey-hole. Nice one. Very nice one in fact. And it leads me to think what use of the One Step Remove I can make in the screenplay I’m currently working on…