The Doctor talks to Ambril and Chela to try and stop the 500th anniversary celebrations. A possessed Tegan finds herself in Dugdale's Hall of Mirrors to where she summons Lon. The Doctor and Nyssa return to the caves.
| Creator | C. E. Webber |
|---|---|
| Actor | Sylvester McCoy, Sophie Aldred |
| Country | United Kingdom |
| Production | BBC |