More from my memories: the "face attacker" kills people, has miniature needle inside it, and leave silver(hope so silver, we had a B&W television then) colored, vein like pattern on the victim's face. The TV show begins(or ends) with moving forward in a metal tube, while you see the credits. Probably it was on Sky Channel. Sry I was 5-6 years old, thanks for every help.
It sounds like you're describing the 1975 Doctor Who episode "Revenge of the Cybermen":
- Face attacker: No legs, like a smaller snake with metal coating, half meter long, leaves colored vein-like pattern on victim's face = Cybermat, third generation, according to this site:
- The opening/closing credits of the Tom Baker era Doctor Who moves through a trippy tube-like thing:
Also, Cybermats scared the heck out of me when I was a kid.