* THE KILLING. Netflix.

No, it really can't be killed. The twice-canceled series starring Mireille Enos and Joel Kinnaman as Seattle homicide detectives - now linked by a terrible secret - has been brought back by Netflix for six (supposedly) final episodes, all of which were released for streaming Friday. I didn't want to get drawn back in, but the four I've seen are intriguing enough to make me want to see if Season 4 can, at last, stick the landing. And at least on Netflix, I won't have to wait weeks to know.

* THE STRAIN. 10 p.m. Sunday, FX.

A clandestine autopsy shows CDC researchers a little more of what they're up against in Guillermo del Toro's horror series, while one member of the team has a confession.

* HELL ON WHEELS. 9 p.m. Saturday, AMC.

All aboard? Season 4 of the series about the building of the first transcontinental railroad gets underway.

* THE LEFTOVERS. 10 p.m. Sunday, HBO.

In a summer with more good TV drama than any reasonable person can handle and still crack a beach book or two, it wouldn't be surprising if this one has already been left behind on your DVR. For those still hanging in, though, this episode, which focuses on Nora (Carrie Coon), who lost her entire family in the Departure, takes her - and the series - to places the book never reached.