The Strain

Strigoi that cannot speak, pushing their thoughts into the minds of their victims, are one of the eeriest touches in del Toro and Hogan's novels, and the show drops them. That silence says a lot about the books as a whole. They are stranger, colder and more willing to go somewhere unexpected than the series. The trilogy is also the only place to find the story as its authors first built it: events in their original order, Nora Martinez alive to the last page, and an ending that turns from epidemic thriller toward something angelic and religious. For viewers who felt the show's final seasons drifted, the books offer a tighter, more coherent version of the same outbreak, with a conclusion the screen never attempted.

Guillermo del Toro and Chuck Hogan co-created the series from their own trilogy, and they still chose to depart from it. Across four seasons the show covers all three books, but the finale leaves out the angelic ending that closes the trilogy, a conclusion Screen Rant describes as even stranger than what the show delivered. Readers get a more overtly religious, otherworldly resolution than viewers do. The sharpest character change is Dr. Nora Martinez, who is killed at the end of season 2 but survives to the end of the books. Hogan said the producers made that call to reenergize the show and don't feel bound by the source. The series also adds two characters who don't appear in the novels and works them into the main story. Season 1 follows the first novel fairly closely. After that, del Toro and showrunner Carlton Cuse deliberately reorder events and drop some altogether, with Cuse warning that readers expecting the books' version will be wrong, though some book elements carry through to the end. Even the vampires work differently. The show's strigoi speak aloud, while in the books their bodies can't produce speech, so they project their thoughts instead.