In Time Reef they find the TARDIS missing pieces and Thomas Brewster refuses to explain where he has been, lastly the group crashes into a time reef
The Doctor and Nyssa have returned to the TARDIS to find it missing various pieces of equipment and its dimensions unstable. Thomas Brewster refuses to explain where he has been since he "borrowed" the TARDIS and what has happened to it. Drawn by a distress beacon, the TARDIS crash lands on a time reef where the interior subsequently implodes, leaving the companions stranded. 
