: While officially titled Le speranze di Zetar on many Italian releases, it has also appeared under titles like Le luci di Zetar (The Lights of Zetar) or Un vampiro a bordo .
The USS Enterprise encounters a strange, colorful energy storm while transporting Lieutenant Mira Romaine to Memory Alpha, a planetoid acting as a galactic library. The storm is revealed to be a collective consciousness—the last survivors of the planet Zetar—who seek a humanoid host to inhabit so they may live again. They choose Mira Romaine, leading Scotty, who has fallen in love with her, to fight to save her from the possession. Italian Context
: This episode introduced the iconic central library of the Federation, which later became the namesake for the real-world Star Trek Wiki .