This stark and unsettling photograph shows London policemen wearing gas masks during a civil-defense training drill in 1939, as Britain braced for the looming reality of modern warfare.

With Europe on the brink of catastrophe, London had already begun to resemble a city under siege. Parliament was in session to grant emergency powers to the government, evacuation plans for civilians were in place, and air-raid precautions reshaped everyday life. Chemical warfare—still a vivid memory from the First World War—was widely feared, and gas masks became symbols of a new, terrifying era.

Here, uniformed policemen stand in disciplined formation, their faces obscured by respirators, transforming familiar guardians of public order into anonymous figures of wartime readiness. In the event of air raids, these men would be responsible not only for maintaining order, but for protecting civilians, enforcing evacuation procedures, and responding to chemical threats.

The verso bears an original International News Photo caption dated August 24, 1939, just days before the outbreak of the Second World War. The caption’s grim line—“A policeman’s life is not a happy one”—captures the emotional undercurrent of a city preparing for war while still at peace.

This image freezes a haunting threshold moment: the last calm before Britain entered the most destructive conflict in human history.

A powerful visual document of pre-war anxiety, civil defense, and the transformation of everyday life under the shadow of total war.