Melanie Sanger ("Mel") is a middle aged hospice nurse who struggles to accept an undeniable truth — all of her patients are going to die. Still grieving the death of her husband in her own facility, Mel looks to start over, taking a job as a hospice nurse in a futuristic Line City in the middle of the Mojave desert nicknamed the Silver Castle. Her dream job quickly deteriorates into a nightmare when she meets Celwyn — a mysterious man claiming to be a Knight of a secret organization in a millennia old battle against vampires — who insists he needs her help to battle dark forces at work in the Castle.
Mel must soon fight for survival after the Castle's hospice is attacked and the Line City is thrown into chaos. Mel journeys with Celwyn through the powered down Line City, attempting to not only save herself, but one of her elderly hospice patients who is bitten by a vampire, and two young girls she can't bear to leave behind.