Paul Nodel's shaved eyebrows in Double Helix (1997) suddenly grow to their natural length when there was a not sufficient time difference between the two episodes (approximately 15 minutes) for this to occur. Similarly, his father Dr. Nodel's beard is noticeably longer than in the previous episode.
Dr. Nodel's first name is given as Eric. However, it was previously stated to be Martin in Double Helix (1997).
A few minutes after the recap and before activating the switch and after he says " pay attention this adventure is just beginning ".You can see in a face close up of the Dr. Martin Model that his mustache is a prop... the mesh is visible.