Star Trek II: The Wrath of Khan (1982)

In Nicholas Meyer's superior sequel to the first installment:

• the frightening scene of genetically-engineered superhuman Khan's (Ricardo Montalban) description of horrifying Ceti eels that he placed into the ears of crew-members Officer Chekov (Walter Koenig) and Captain Terrell (Paul Winfield): "their young enter through the ears and wrap themselves around the cerebral cortex" - to control their minds: "This has the effect of rendering the victim extremely susceptible to suggestion. Later, as they grow follows madness and death"
• the scene of Enterprise Admiral James T. Kirk's (William Shatner) conversation with a gloating and vengeful Khan when he believed he had stranded Kirk on the barren planet of Regula: (Khan: "I've done far worse than kill you. I've hurt you. And I wish to go on hurting you. I shall leave you as you left me, as you left her -- marooned for all eternity in the center of a dead planet. Buried alive. Buried alive." Kirk (shouting back): "KHAAANNNN! KHAAANNNN!")
• the revelation of the Genesis Cave - opening into a lush biosystems paradise
• the great sacrificial death scene of pointy-eared Vulcan Captain Spock (Leonard Nimoy) from radiation poisoning to save the U.S.S. Enterprise (and provide it with warp speed) after the venomous Khan decided to blow up his own spaceship with the Genesis torpedo device and thereby also destroy the Enterprise
• Kirk's simple "No" as he watched Spock die
• the intimate scene of Kirk's heartfelt eulogy for Spock during a funeral ("Of all the souls I have encountered, his was the most... human")
• Spock's send-off into space to orbit a newly-birthed planet