This game is a sequel to Mulldoon Legacy, and is smaller.
In an interesting take on the sequel concept, you arrive after the events of the first game, and the effects of your predecessor's actions are everywhere. Items they dropped, doors they opened, things they moved.
Everything is slightly different in the museum, though; a sort of darker version of things. This game expands on the mythology a bit, while still being confusing.
If you liked the first game, you should try this one for sure.