31. The Debut of the Impossible Girl
From: "Asylum of the Daleks"
Premiere: September 1, 2012
Not long before this cinematic epic of a season-opening episode aired, the Doctor Who team announced that Jenna-Louise Coleman had been cast as the Eleventh Doctor's new companion, starting after the midseason departure of fan favorites Amy Pond and Rory Williams. Try to imagine the shrieks of delighted recognition, then, when Coleman turned up here, unannounced, as crafty, doomed Oswin Oswald – a clever gambit miraculously unspoiled by audiences who saw advance movie-house screenings of the episode.