Spoonerisms are fun. Named after the Reverend William Archibald Spooner (1844-1930), spoonerisms are funny word plays based on switching the opening sounds of two words. Queer Dean, is, then, Dear Queen.
This story, from This Week (March 8, 1953) is based on spoonerisms, specifically those spoken by Ellery’s beloved Harvard professor, Matthew Arnold Hope, named, for some unknown reason, after the poet Matthew Arnold (1822-1888).
Here is one example of Professor Hope’s spooneristic style:
All those who persist in befouling their theme papers with can’t and other low expressions not in good usage are warned for the last time: Refine your style or be exiled from this course with the rest of the vanished Bulgarians.
Which does sound like Matthew Arnold’s cultural theory, but I digress. One might expect Ellery to go searching for the vanished Bulgarians, where ever did they disappear to? Instead, this story follows a very different mystery: a con artist and a clue from a severely injured (but not dead, yet) man, which turns out to contain not one, but two spoonerisms.
Meanwhile, the Bulgarians remain vanished.
Reading Ellery Queen 
This seemed pretty easy for one of their mystery stories. The solution is hinted at in the title. We also see the Harvard inconsistent
reference since he did not mention being from Harvard three years before in Double Double. Amazing how well Julian Symon’s retcon works.