Purgatory's Key
The conclusion to the special 50th anniversary trilogy!

Purgatory's Key is a Pocket TOS novel – the third and final novel in the Star Trek: Legacies trilogy – written by Dayton Ward and Kevin Dilmore. Published by Pocket Books, it was first released in .

Summary 
From the book jacket
An all-new epic trilogy commemorating 50 years of Star Trek.Eighteen years ago, the Starship Enterprise thwarted an alien invasion from another universe, and Captain Robert April took possession of the interdimensional transfer device that made it possible. Since then, each captain of the Enterprise, from Christopher Pike to James T. Kirk, has guarded this secret with his life.

Now, Romulan agents have succeeded in stealing the device and using it to banish Ambassador Sarek and Councillor Gorkon to an unknown realm in the midst of their groundbreaking Federation-Klingon peace negotiations. With time running out as interstellar war looms in one universe – and alien forces marshal in another – will Captain Kirk and his crew preserve the tenuous peace and reclaim the key between the dimensions?

 Background information 
 The historian's note indicates that this takes place in early 2268, immediately after the events of Best Defense''.
 Cover art and design by Alan Dingman.

Cover gallery

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