When the Smalls first move into the Dies Drear house, they aren't sure they'll be free to enjoy it. Someone, or something, seems to want them out. The house itself is the embodiment of this theme. A hundred years before, it was a shelter for people running from slavery to freedom. That's the ultimate freedom and confinement scenario. The story celebrates freedom of the mind and the body. It asks whether knowing the past can help us find freedom in the present and in the future.
At first, Thomas is trapped by his suspicions of those around him; as the story progresses he becomes free of his suspicions because he learns the truth.
The Darrows and Mr. Pluto are both trapped by Dies Drear's treasure.
Mr. Pluto and Mayhew begin to free themselves from the past by focusing on their lives together in the present.