 The documentary follows the fictional scientist Dr. Howell, played by Glenn Conroy, as he travels from his London hotel room to his laboratory in New York City, and shows how each scenario affects his journey as well as those around him, with various experts providing commentary on that specific disaster as it unfolds.After each 'End Day' runs its course, the day repeats, this time with the next scenario panning out.The following descriptions of the program were released by the BBC