Jason Isaacs is very good but Gillian andersons accent comes and goes which left me totally confused! I've read the book and expected more from this. There was no explanation of where they were along the path or who and where Polly popped up from and why she didn't help them at the beginning of their struggle. Also the book explains the improvement in Moth's health, which is the main benefit from this walk.
When I read the book I thought they were totally irresponsible in walking the path with his condition and I still think it was a ridiculous way to deal with this situation.
There are two more books when they go off walking and they may be doing it for their own reasons but I think they are selfish to go walking like this and could put rescue teams at risk if they fall into serious trouble.