10 More Times Star Trek Accidentally Filmed Things You Weren't Meant To See
8. The Makeup Artist In Data's Dream
In part one of the Next Generation episode Birthright, Data started having "dreams" about his creator, Doctor Soong.
During his second dream of the episode, after he turned into a bird and flew past Dr. Soong, June Abston Haymore, a makeup artist for the show, appeared briefly sitting in front of a door. She was most likely on break and didn't realise that she was in the shot.
She was digitally removed from this scene in the remaster of the episode, but can still be seen (though less noticeably) in the first dream sequence.
There have been a number of other instances where members of the production crew have accidentally shown up in scenes, but given that this sequence was all an illusion inside of Data's mind, her appearance is even harder to write off. Either way, the dream sequences in this episode were trippy enough that not many people noticed June sitting there.