The Eternals enter into their third installment of the series as a dark figure at the front door casts an ancient incantation on them. Eventually, Lucy wakes from a dark sleep and finds herself fourteen years into the future in Colorado. The most startling part for her isn't that they have moved into the future but the fact that she's somehow been transformed into a blood-guzzling vampire. Soon, Paulo, Paris and Emmitt find themselves in similar positions, trying to find their way back to each other.

As the years pass by, the Eternals discover that every other supernatural creature on earth has also been chhanged into something else through a domino effect. The Eternals are introduced to Changelings, werewolves, mermaids and even an alien race. Again, the Scarlett witches play an intricate role in helping the Eternals while also trying to recover their own family.

When Lucy realizes she has the gift to help others, she forms committees to help the species unite with their own kind. Paris finds himself deep in the Himalayan mountains once again, living in the Lost City, where he is treated as a traitor and a lowly vampire. As one of the Eternals finally figures out who cast the ancient spell, they try to find a way to reverse it. The story weaves back and forth through each life, leaving only more fear and questions as time reveals itself.