Doctor Who And the Phantom's Song

When the TARDIS strands the Doctor in a 19th century opera house things seem strange. But they get even more so when he descovers that things are not quite as they seem, The Phantom Of The Opera is on the prowl, seemingly controlled by Missy. But if that wasn't enough he has to deal with an impending invasion. Time is running out, not something a Timelord usually acknowledges...