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I was watching a Person of Interest episode a few weeks ago.
I noticed that the main star, Michael Emerson (who plays Harold Finch) was credited in the "With" part of the Starring credits.
Also, despite being in most of the season, John Nolan was credited as Guest Starring, as was Julian Ovenden, despite them being series regulars.
On Supergirl, despite being a series regular, Jenna Dewan Tatum gets Special Guest Star billing even though she has been in most of the episodes.
On The Catch, Elena Rusconi and Jamie Van Dyke (a woman, like Jamie Lee Curtis) were credited as Guest Starring despite being series regulars in the show.
How is this decided with the credits who gets to be in With/And Starring, Special Guest Star, Guest Starring?
If a show had 23 actors in it as regular characters [like the British show Casualty, Doctors have large casts] and they were in it nearly every episode [about 90-95% of the time] how do you think they would credit the actors? This hypothetical show would be a crime drama of sorts, like CSI or The Catch.
50% starring, 50% guest stars, or some other means?
Also, do some actors not named in opening credits, but who are main characters/integral to the show, just get shafted to the end credits if they can't fit them in the opening credits?
What shows have the longest list of Starring, And Starring etc.
Is it decided based on the actor's level of fame or some other way, is it arbitrary?
I would appreciate it if anyone knows why this is so.