Star Trek: The Animated Series (1974)
It seems a little unfair to include the animated spin-off of the original 60’s Star Trek here, as it exists more as a curiosity than continuation, though it is largely regarded as canon. And fun fact, it actually won an Daytime Emmy Award for Outstanding Entertainment Children’s Series in 1975 for the episode ‘How Sharper Than a Serpent’s Tooth’.
Star Trek: The Animated Series featured all of the original cast in voice roles, except poor Walter Koenig as Chekov, who was cut for budgetary reasons but did get to write an episode. While the series did take advantage of the medium with some non-human characters, it lacked the imagination to go beyond the premise of the original series and a real classic like its predecessor – or successors.
Mind you, the second episode ‘Yesteryear’, which saw Spock travel back in time to save himself as a youth after being erased from existence, did serve as an inspiration for JJ Abrams’ 2009 movie reboot.
Deep Space 9 is absolutely the best series in Star Trek, it’s cast are brilliant, their stories creative, and the Dominion War is still the best thing that Star Trek has ever done. I’d also put forward that ‘The Battle of AR-558’ is possibly their best episode.