One of the biggest mysteries driving Season 5 is the bizarre disappearance of Polly Cooper (Tiera Skovbye) as well as the urban legends surrounding the mythical Mothmen who haunt the Lonely Highway. Episode 17, “Dance of Death,” reveals that the Mothmen legend is actually tied to the Blossom family, of course. Nana Rose (Barbara Wallace) reveals that her late husband kept sleeping with a number of women who worked in the Thornhill mansion — and their illegitimate children were given away to the cave-dwelling Starkweather family.
The Blossoms are all about making sure the public perception of the family is squeaky clean, especially since the family runs the Blossom Maple Syrup farms, so it isn’t surprising that Nana Rose was keen to sweep the scandal under the rug. Unfortunately, the Starkweathers’ surroundings didn’t make for the best place to raise children, and they created the Mothmen legend to make sure the Riverdale citizens didn’t come looking for them.
Obviously, their isolated home made it difficult to survive, and the Starkweathers started robbing passersby on the Lonely Highway — but their time in the wilderness left them twisted and rotten. Eventually they started hunting women for sport, and unfortunately, Polly Cooper was one of those women. Jughead figures out that Old Man Dreyfus is her killer because the Mothmen corpse the gang finds has Blossom’s DNA in it, and the shady caretaker knows too much about the Mothmen.
Sorry “Riverdale” fans, the Mothmen aren’t aliens after all. But how about a witch?