3: Stowaway Slaves: Book 3 by David Grimstone
Decimus Rex has escaped Arena Primus in the company of a fellow slave, Olu Umbika. Together, the pair has managed to do what no one else has ever done - flee the clutches of Slavious Doom. As expected, the overlord is furious and demands their immediate capture. A frantic and determined search follows. From the wild dogs running riot in the sewers, to the soldiers scouring the towns above, it seems only a matter of time before they are caught.