When Nicholas Meyer signed on to direct Star Trek II, he actually had little knowledge of what he wanted. To prepare, he watched several episodes, including this one. In fact, if someone had never watched Star Trek, this is an episode I would show.
The story begins when the Enterprise finds the starship Botany Bay. They board the ship with historian Lt. Marla McGivens accompanying them. When they beam onto the ship, they discover there are inhabitants in suspended animation. These are the notorious Khan Noonian Singh and his followers.
Everyone is intrigued with the idea of reviving Khan and his followers, despite their reputation. I like how Spock is bewildered that Khan is actually revered despite his tyranny. This is realistic. There are many notorious people who are still admired to this day.