Seeing them back-to-back was much like seeing the three Lord of the Rings movies back-to-back. The day flew by.
Did they use the same cast for all three plays? Because that would be impressive, and a little inhumane.
They did, more or less. Some people were in only two of the three, some major characters were in all three, and some rotated roles from one to the next. This details the actor to character relationships nicely.