Preppers Shop UK, the nation's "number one preppers ... out bags" (essentially goodie bags packed with survival tools), gas masks, biohazard suits, decontamination apparel and "virus control ...

Now put your books down…and get your gas masks out. Quietly. Now take them carefully out of their boxes - no, no, Isobel, don't drag at it…you show her how to do it, Margaret, will you.

A sign hanging above the doors to the gas chamber reads, "Even the brave cry here." A dozen at a time, Marines are ushered into a small, dark, brick room. A thick haze of o-Chlorobenzylidene ...