Warning: Spoilers ahead for Doctor Who season 15, episode 2, "Lux."Doctor Who season 15, episode 2, "Lux," is the second time in a row that Russell T. Davies has referenced an iconic installment from David Tennant's time as the Tenth Doctor, but any perceived ridicule has only ever been in jest. The legendary episode in question introduced a race of monsters that quickly became one of Doctor Who's most commonly recurring villains, which is a category of bad guys that has been difficult to introduce in the revival era. Years after its 2007 debut, Doctor Who's Disney era is still paying homage to the story.