Seeded — Adrienne Jones

Callum Doherty picks up a trinket from an odd jewelry dealer at a hippie music festival, "a good luck charm" the man tells him. But days after clasping the pendant around his neck, he discovers it can't be removed. After visiting every locksmith and jeweler in the city with no success, he reluctantly accepts he's stuck with the thing. But when an overwhelming burst of success transforms him into a wealthy superstar overnight, he wonders what other sudden life changes are linked to the pendant--like the terrifying shapeshifters he spies following him through the city, slinking around his property, and watching him while he sleeps.