Is it from a cartoon?

blueluigi wrote :

Is it from a cartoon?
-end quote

Nope

Clues so far:

The character has more than one name and a title.  The first name first
initial can be either a P, R, or B.
The show aired in the 1990s
Not a super hero
The different names are not alter egos or split personalities (to be fair the character does use disguises, or changes appearance, sort of)
It is not from a cartoon

Bonus Clue:

From a literary character. The alternate names are never used in the show except for the credits and the literary source. The character's title and one name are used in the show.

Is the letter used in the show "P"?

Vaporman87 wrote :

Is the letter used in the show "P"?
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Yes

Literary character, huh?
Was the show a period piece?

jkatz wrote :

Literary character, huh?
Was the show a period piece?
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Yes. The show is set in two different time periods. 

Is it a science-fiction series?

blueluigi wrote :

Is it a science-fiction series?
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No, well some aspects would be considered sci-fi but that is definitely not the main genre. 

Clues so far:

The character has more than one name and a title.  The first name first initial
can be either a P, R, or B.
The show aired in the 1990s
Not a super hero
The different names are not alter egos or split personalities (to be fair the character does use disguises, or changes appearance, sort of)
It is not from a cartoon
From a literary character. The alternate names are never used in the show except for the credits and the literary source. The character's title and one name are used in the show.
The letter used in the show for the first name is "P"
The show is set in two different time periods. 
Some aspects would be considered sci-fi but that is definitely not the main genre.

Bonus Clue:

The character is a villain and the person playing the character has been a villain in several cool films from the 70s, 80s, and 90s in different roles.