The "light bulb challenge"

[at Quark's]

Inspired by this somewhat silly (but still fun) set of parodies about changing a light bulb in TOS/TNG/DS9/VOY/ENT style:

http://www.eviloverlord.com/parodies/

I was thinking: is is possible to come up with a quintiplet of actual TOS/TNG/DS9/VOY/ENT episodes that center around the same - rather specific- theme, yet each 'member' episode being quintessentially TOS/TNG/ .. etc ?

(I'm stating the theme should be 'rather specific' because of course there would be no real challenge in mentioning a set of episodes under a general theme like "exploring the human condition while purportedly exploring outer space")

(Haven't found any good examples myself yet, but I'm sure there should be some.)

 

[JirinPanthosa]

Return To Tomorrow, Lonely Among Us, The Assignment, Cathexis, The Crossing

City On The Edge Of Forever, Time's Arrow, Past Tense, Future's End, Most of Enterprise