A flash of blinding light followed by a mushroom cloud changes life for ever in the UK, as a nuclear winter descends upon the country, a giant ash cloud severely restricting daylight, leaving everything bathed in twilight, no matter the time of day.

Glenn, a regular guy who is addicted to watching YouTube videos, Catarina, a Brazilian on vacation in the U.K., and Princess, a disabled stray dog chance upon each other after a nuclear attack and travel west, to Land's End, in an attempt to get as far away as possible from ground zero. With no national infrastructure left, it's every man and woman for themselves. With vehicles disabled by EMPs,as a result of the explosion, their only choice is to make their journey on foot.

With a journey of almost three hundred miles ahead of them, a journey that's fraught with danger, not only from brutal invaders but also from other citizens who, in their desperation to survive, resort to theft and murder.,the odds are stacked against the trio reaching their destination in one piece.