What exactly it’s for is another matter altogether. A little backstory for a couple of slightly under-developed characters? Fine, but why not incorporate that into the drama itself? The joining of a few dots in the plotting? Maybe, but that begs the question of whether this is intended as an episode in itself or a sort of classy DVD extra, independent from ‘Dancing on the Edge’s actual narrative structure.
Ultimately, one can’t help but suspect that a writer less renowned than Poliakoff wouldn’t have got away with this. At some point, someone would have suggested that six hours should be enough to tell the stories of those involved. And they’d have been right. If you saw the series through to the end, you won’t want to miss this. Don’t be surprised if you feel like you’re being taken for a ride, though.