"Cocoon" is a two-part episode. So 2 hours total.
Here's your episode guide:
https://www.imdb.com/title/tt0062568/episodes?season=1
The character of Danny was played by a different actor (Tim O'Kelly) in the pilot than in the rest of the series (James MacArthur).
The governor also...Lew Ayres vs. Richard Denning.
Lot of great episodes. Season 3, Episode 11 "Over fifty? Steal." featuring Hume Cronyn is one I really liked.
It was great watching these today, although I missed the last one because I had promised to bring a fish dinner over to Mom. Mom turns 99 next month so an easy decision to make there....