The story is set in 1938 and follows Lee Yeon (played by Lee Dong-Wook), the mythical nine-tailed fox, as he gets pulled back in time to this era. He must navigate a chaotic historical period while facing supernatural challenges, old enemies, and unexpected allies. The main plot revolves around Lee Yeon’s attempts to return to the present while encountering various characters, including his half-brother Lee Rang (played by Kim Bum) and Ryu Hong-joo (played by Kim So-yeon), an old friend and potential adversary.