Well, since the previous episode had resulted in a new regeneration after an epic battle, it would have been a bit redundant and over-the-top to go for another earth-shattering conflict for Episode 100, so I finally settled for a more personal story - with shades of The Next Doctor, but without Cybermen (or any other major bad guys for that matter - and no, I'm not turning into Steven Moffat).
Episode 9: The Other PenelopeA funny thing happened on the way to Avalon… Her TARDIS takes the freshly-regenerated (and still slightly disoriented) back to the seaside town of Weston-super-Mare – where she first met the Doctor, four lifetimes ago, in 1907. But it’s now January 1930 and the Time Lady must solve new mysteries. Why has her timeline brought her back near the majestic Grand Pier at this precise point in history? What is the retired H.G. Jago doing here? And who is that other woman calling herself Penelope Ashworth? A tale of identities and memories.