The Turnpike Troubadours bump into some old friends on the Oklahoma band’s new song “The Mercury,” which premieres today on Speakeasy.

The rugged barroom stomper rides a brawny guitar riff over a tough sounding beat. Fittingly, the song is indeed set in a barroom—the Mercury Lounge, in Tulsa—where listeners will encounter some recurring characters that have popped up in songs on the Turnpike Troubadours’ previous albums.

“The...