John Wyndham's classic tale of monsters from the deep, alien invasion and ecological disaster comes alive in this full-cast BBC radio dramatisation. At first, the fireballs seemed to be nothing more than a dazzling display of lights in the sky, plunging into the deepest oceans and disappearing without trace. But when ships started sinking inexplicably and the sea-lanes became impassable it seemed that the world was facing a threat of unprecedented proportions.