I had to re-bake my scene several times before getting the look that I wanted. This last time, the scene looks great, but my characters are now very dark and the playable character is completely black. He lights up only when the directional light hits him.
Saying this makes me realize the problem (sort of): All the spotlights from the room's interior were probably baked while the characters were turned off, making their solution require the only real-time light in the scene in order to be seen.
Still, I didn't think the characters would be involved in the lightmap data? How do I redo the lights just for characters and moving objects? How can I fix this and keep the scene lighting?