The character of Quentin Collins was created at the request of Jonathan Frid, who asked that a second villain be brought in to lighten his workload.
For more than a year and a half, the characters of this show used almost every possible phrase to refer to Barnabas Collins ("He's not alive!", "He's one of the undead.", "He walks at night, but he ain't alive.") It wasn't until the 410th episode that the word "vampire" was used on the show.
Originally, David Selby donned fake sideburns for the role of Quentin Collins, but eventually he grew his own, so he would no longer have to endure the make-up.
Due to the grueling five-shows-a-week schedule, the expense and the difficulty of video editing in those days, most scenes were shot in a single take. Actors and actresses routinely flubbed their lines and searched for the teleprompter, set pieces collapsed, props malfunctioned, crew members walked into shots, microphones and secondary cameras got in the way, and it all wound up being preserved, because the production team figured each episode would only be seen one time.
The producers planned to run the 1897 storyline for three months, but it was so popular that they ended up expanding it to eight and a half months.