When Frye suffers a workplace injury that costs him his left arm, he is overjoyed when the company doctor tells him it can be reattached weeks later. Sure, it's longer than he remembers, has signs of decay and seems to have sea shells and teeth marks in it, but hey, nobody's perfect.
As he returns to work things have taken a change to the more occult, Frye must unravel the mysteries of his new job, and his new arm before one or both kill him.
The Reattachment, riffs on Hands of Orlac and other amputation horrors by way of Franz Kafka along with an element of eldritch weirdness.