Tread Perilously wraps up its look at Doctor Who's 23rd season, "The Trial of a  Time Lord," with part 13 (by Robert Holmes) and part 14 (by Pip & Jane Baker) -- collectively known as "The Ultimate Foe."

When the Valeyard enters a charge of genocide against The Doctor, Mel and Sabalom Glitz are pulled out of time to appear as witnesses. Their testimony is never taken into the record as The Master appears to break up the trial and accuse the Valeyard of malpractice ... and of being The Doctor himself. It all leads to the Matrix, which the Valeyard was manipulating the whole time, as part of a plot by the Time Lord High Council to prevent The Doctor from revealing the truth about Ravalox. It is about as confusing as you might think.

Justin wants to join the Liverpool Doctor Who Appreciation Society. He and Erik try to figure out The Master's actual motivation across the two episodes. Justin praises the return of Sabalom Glitz and actor Tony Selby. Erik somehow figures out how the Time Lords tying Thetans to volcanoes on Earth led to The Doctor's trial. "A bob for a tuna?" becomes your new favorite bit of Cockney slang. Erik and Justin begin breaking a new BBC prestige series called The Adventures of Eustace Popplewick, and Justin suggests classic Doctor Who would work better as three-part stories.