Turtles... IN SPACE! The brothers make an interstellar journey to different planets in Dimension X to save key witnesses in the Trial of Krang from assassination! Weird new characters, places, and events abound! This mini-series introduces an all-new villain, Hakk-R, into the world of the TMNT, directly affecting the events of the main ongoing series in this dimension-altering adventure.
— Description from Comic Vine community (comicvine.gamespot.com).
