Iain Glen had a truly terrible time filming the major battle against the Army of the Dead.
"It was the most unpleasant experience I've had on Thrones," he told EW. "A real test, really miserable. You get to sleep at seven in the morning and when you wake in the midday you're still so spent you can't really do anything, and then you're back. You have no life outside it. You have an absolute f—ked bunch of actors. But without getting too method [acting] about it, on screen it bleeds through to the reality of the Thrones world."