Murder, they wrote

Evil knows no bounds these days on TV, a medium that seems determined to take all the fun out of the horror genre. "Slasher" is the latest grim effort, with Katie McGrath ("Jurassic World") trying to figure out why copycat murders have gripped her small town. It's times such as this that one pines for the comedy stylings of Chucky from "Child's Play."

8 p.m. Friday, Chiller

No myth

After 13 years and more than 275 episodes, "MythBusters" is solving its last mystery. The finale deserves credit for debunking a lot of urban legends and making us nostalgic for our junior high science experiments, although I'm still ticked that hosts Adam Savage and Jamie Hyneman never tackled the mystery of how my dryer always manages to make one of my socks disappear.

7 p.m. Saturday, Discovery

Shuttering the manor

In the final analysis, the most fascinating character on "Downton Abbey" wasn't one of the bickering sisters or even Maggie Smith's Dowager. It was the automobile. How did a sputtering engine overtake once intriguing characters? Check out my take in Sunday's Variety section, which is tied to that night's two-hour series finale.

8 p.m. Sunday, TPT, Ch. 2

Politically incorrect

The fourth season of "House of Cards," now streaming on Netflix, may be a shining example of a show overextending its hand, but that's not stopping its star from doubling down on Washington politics. Kevin Spacey serves as narrator and an executive producer for "Race for the White House," a new series that dissects some of the most contentious presidential campaigns in U.S. history. The duels are compelling, most notably one revealing that "Honest Abe" wasn't above signing off on dirty tricks.

9 p.m. Sunday, CNNNeal Justin