.


And inevitably given its success, a sequel TV movie less than a year later.



The Night Strangler (1973)




https://en.wikipedia.org/wiki/The_Night_Strangler_(film)



Equally good, equally terrifying, equally funny. Also written by Richard Matheson.
Starring Richard Anderson as the immortal strangler. Who very soon after became Oscar Goldman, the co-starring government boss of Steve Austin tn the long running very popular Six Million Dollar Man TV series.

And from the above 2 TV movies, The Night Stalker then evolved into a 20-episode very successful The Night Stalker TV series, ended partly because the author of the original story sued for copyright infringement, over expanding his story and characters without his permission, and while the initial 2 movies were enormously popular, the series episodes declined in ratings over the series run, largely due to running in a bad time slot, Friday nights at 8 PM, when the targeted younger audience wasn't home watching TV.

I was surprised to read it had a dip in ratings as the series ran, despite achieving enormous cult status later, after its cancellation. And that Darren McGavin, who is best known for this series, actually wanted out of his role in the series, because he was exhausted by the workload of doing the series, and did not feel adequately compensated for his production and script revision work.
Most or all of the 20 episodes are online at Youtube, with great HD reproduction, accessible at the above two linked movies.
There were 6 more episodes planned for the series, scripted but not produced.

https://en.wikipedia.org/wiki/Kolchak:_The_Night_Stalker ( series, 20 episodes, 1974-1975 )