The whole business with the keys and the graves
I couldn't follow that at ALL. I have a learning disability so understanding these things is very hard for me.
Could someone tell me what that was all about? Much obliged.
***SPOILERS***
At the very beginning of part 1, John Jasper is experiencing opium-fueled nightmares of strangling his (supposed) nephew, Edwin Drood. The big reveal in part 2 is that John Jasper had actually already strangled his father, Edwin Drood Sr. (father of both young Edwin and himself) about a year before our story begins. His crime was relatively easy to conceal because Edwin Drood Sr. has been presumed dead for 8 years...and (we're asked to believe that) no one has seen him in all that time: apparently he was in hiding for all of those years and had just decided to reveal himself to his legitimate son (and heir), Edwin Drood Jr., when Jasper recognized him in the church and (in a fit of jealousy, rage, and wounded pride) murdered him on the spot.
A bit hard to swallow, but anyway... Where the crypts and keys come in is that after murdering his father, Jasper hastily concealed the corpse in the Sapsea family crypt, which was close at hand and newly open (or newly built, I'm not sure which) because Mr. Sapsea's recently-deceased wife had just been laid to rest there.
Still with me?... In part 1, Mr. Sapsea, now mayor of the town and luxuriating in his new (self-)importance, has just written a grandiloquent inscription to be engraved over the Sapsea crypt, which means unlocking its gate; Jasper, fearing that the corpse of his father may be discovered by one of the workmen, knows he has to act fast. So he coerces Dardles (the crypt-keeper) into giving him a nocturnal tour of the crypts, and then knocks him out with drugged wine. From Dardles' key-ring he steals the key to the Sapsea crypt and...(according to the flashbacks in part 2), he then moves the body of Edwin Drood Sr. to the Drood crypt, for which (I'm guessing) Dardles also had the key. I believe Jasper then disposed of the Drood key; but the minor canon still retained a copy, which is how the Drood crypt is finally opened at the end, revealing the mystery.
I also found it hard to follow, and this is only my best guess. :-)
He may have been hiding in Egypt, which would probably have been easier to manage.
What troubled me is that it takes two grown men to shift the cover of the tomb, but we're to believe Jasper could do it all on his own?