Of all the unsettling sights on this gruelling polar expedition, perhaps the most ominous of all is nowhere near the ice. Rather, it’s in menu, where the narrative branches of this choice-driven adventure are clearly laid out. Most are fairly short, ending at points where key decisions took us down a different path; points from which we are able to continue should we choose to turn back. But the one we are currently heading down, more than 30 weeks in, is terrifyingly long and straight, each previous week represented by a padlock that tells us we cannot go back from here. Several of our crew are freezing; a few are malnourished; a handful deeply demoralised; two are no longer
