Michael B. Jordan wears an Elgin Trench Watch

October 1932, Clarksdale, Mississippi. Twin brothers come home from Chicago to open a juke joint, and Ryan Coogler has Michael B. Jordan play both of them. The Elgin trench watch belongs to Smoke: a real century-old piece with a steel tonneau case and a round beige dial, black Arabic numerals with a red 12 at the top, on a softly worn brown leather NATO strap. Coogler told prop master Douglas Ware that the twins had served in the 369th Infantry in the First World War, and Ware went looking for a watch that could have come home from that war. The film never says how Smoke got it. Ware had his own theories: maybe he traded a French soldier chocolates or American cigarettes for it, maybe he won it in a card game, maybe he pulled some French soldiers out of a dangerous spot and this was the thanks.

The brand fits the history. Elgin made nothing but pocket watches for the half century after its founding in 1864 and added wristwatches only just before the war, as a piece of equipment long regarded as feminine moved onto soldiers' wrists. Toward the end of the war the company produced three models named for Allied generals, the Kitchener, the Foch, and the Pershing, and sold them to the public after the armistice in 1919.

The props team handed Coogler a few candidates, and the director let Jordan choose. The first pick kept catching on the actor's sleeve, so the Elgin on screen was actually the second choice. A different vintage stand-in covered the bloodier scenes, but the real thing was on Jordan's wrist when the finale put him in the water at dawn, and the crew found out quickly that a century-old trench watch is not waterproof. It could not be saved.