Despite credited as a part of the main cast, James Frain has only one scene in this episode, in which Theo Galavan appears as a corpse (most likely a prop, but still counts as an acting appearance because it required the actor working at least one day with special make-up artists for visual reference).
When Bruce is talking with Dr. Tompkins, his responses to her questions foreshadow his future as Batman.
The fellow floating in the third tube at the end of this episode, missing an arm, is likely a reference to Green Arrow's sidekick, Speedy.
The music during the scene in this ep where Mrs. Fries puts on her necklace is the same music from Batman & Robin (1997) when, in that film, Mr. Freeze reveals his wife in the chamber wearing her necklace.