HBO's Boardwalk Empire fans were delighted when actor Michael K Williams (Chalky White) offered up a photo of himself in a classic 1920s style costume. The only problem? The photo wasn't from the set of Boardwalk Empire.

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"Chilling on set with the homie @mrcolb3rt #Bessie," wrote the actor on Instagram Monday. The caption came alongside a photo of Williams dressed in a brightly colored vest and tie. Boardwalk Empire will be taking place in the 1930s this season and so if his attire looks a little grandiose for the Great Depression, that's because it is.

While a number of fans assumed the pic was from White's HBO prohibition drama, the picture is really from the set of another HBO project, the telepic Bessie.

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On July 11 Variety announced that Williams would be joining the cast of the Bessie Smith film in the role of Smith's husband.

Nicknamed "Empress of the Blues," Bessie Smith was a famed singer of the 1923s and 1930s, which explains why fans of Boardwalk Empire were confused when they saw White wearing a 1920s vest. Written and directed by Dee Rees, the drama is also set to star Queen Latifah (Chicago), Mo'Nique (Precious), Khandi Alexander (Treme, Scandal), and Charles S. Dutton (Secret Window).

As for real pics from the Boardwalk Empire set, fans might just have to wait for the show to air on television. The drama is set to return to HBO for its fifth and final season Sunday, September 7 at 9 p.m. ET/PT.

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