THE MURDERS IN THE RUE MORGUE LEVEL B2.2 (BK+CD)

Two cases of detection for Monsieur Auguste C. Dupin, Poe’s great detective.
Who could have committed the atrocious murders in the Rue Morgue and so how did the murderer get in, or out?
Will Dupin find the purloined letter and save the royal personage? Where is the minister hiding it?