The Last of the Jedi: Underworld

Underworld is the third in a series of young reader novels that chronicle the adventures of Obi-Wan Kenobi and Ferus Olin following Star Wars Episode III: Revenge of the Sith.

Publisher's Summary
A disgraced Padawan returns to the captive Jedi Temple on Coruscant to redeem himself. Ferus Olin has heard rumors that the Empire holds imprisoned Jedi within the desecrated building. Olin and his street-kid partner, Trever, must plunge into the depths of Coruscant's dark and dangerous underworld in order to free the Jedi. The lower reaches of the city planet have become a perilous sanctuary from those fleeing the Emperor's wrath, and navigating its alleyways and corridors may be just as dangerous as a foolhardy mission to breach the temple.