Imzadi is a non-canon Star Trek novel by Peter David, primarily exploring William Riker's assignment to Betazed and his early relationship with Deanna Troi.
Troi's history with Riker had been introduced in the pilot episode of Star Trek: The Next Generation, "Encounter at Farpoint"; this also included the word imzadi, a Betazoid term of endearment usually translated as "beloved".
"[1] Seventy-three-year-old Admiral William Riker is a bitter, lonely man in a slow downward spiral following the death forty years earlier of Deanna Troi, who died of undetermined causes during a peacekeeping conference with an enemy race, the Sindareen.
Will was instantly attracted to her and began to pursue her, though she initially rebuffed his advances, feeling that he was only interested in her physical attributes, and that he preferred quick, thrilling encounters over meaningful emotional intimacy.
While visiting her favorite museum, Deanna was kidnapped by a Sindareen raiding party, and Riker's Starfleet security force shot down their small craft in the jungle.
However, after their return from the jungle, Lwaxana's violent objections to their relationship and Deanna's seeming compliance led Riker to drunkenly fall into bed with another woman.
Struck with a new suspicion, Admiral Riker has an autopsy performed on Deanna's corpse and discovers that she had been murdered via a poison that did not exist at the time she died.
[5] A TrekMovie.com reviewer writing in 2010 about Peter David's later works mentioned that Imzadi remained his favorite Star Trek book of all time.