Triumvirate of Terror! - S3-E8
Continuity mistake: Right at the beginning, the camera closes in on a baseball field. It shows several people standing and walking out in the field and just two standing up by home plate. The view changes to behind home plate and suddenly there are several superheroes sitting and stretching there, and the rest of the field is empty. Then after a shot of Jimmy Olson in the commentator stand, it shows a high view of the field again and the people have all changed again. (00:00:10)