A Sherlock Crossover. A series of strange events, the least of which is a psycho- no wait- sociopathic pony appearing in Twilight's castle and an urgent request from Dragon Lord Ember.
Twilight Sparkle finds herself in a weird room of the Crystal Empire's palace. A library full of spellbooks she has never seen before. It is a little late when she finds out what magic it is.
Hearts and Hooves day. You would think this would be a great time for changelings, but when a queen bites off more than she can chew, she learns something about her species forgotten for decades.
When Trixie begins to hear a voice comfort her in the time her shows are not faring well, she starts to go into other forms of entertainment, with her 'angel's' voice.