The Mystery Cartoon Character Game, ongoing-ier.

King Triton from The Little Mermaid.

Glowworm is absolutely correct, this is King Triton from Disney's adaptation of the Hans Christian Andersen tale, The Little Mermaid. One of Triton's tirades against humans occurs in Ariel's hideaway, where he describes them as "spineless, fish-eating savages." King Triton is clearly based upon the god Poseidon from Greek mythology, also known as Neptune from Roman mythology. And speaking of Neptune, Triton is one of two major moons that orbit the planet Neptune, the other being Mimas. Interestingly, Poseidon is one brother to Zeus; Hades is the other.

I'll give a nice, fresh +1 to Glowworm, some warm condolences to EmeraldIsle (Zeus was close, but he only hates a few select people), and accede control of the board.

Triton is actually a separate deity from Poseidon--his son to be exact, and the messenger god of the seas. Tritons are also used to describe merpeople of both sexes.

Anyhow, on to the next character.
1. There are three of us, and we are rather inept at our trade.
2. An evil spirit brings us a book of magic to help set her free.
3. We are female--but our looks and mannerisms are based upon a well known comedic trio.

I know. It's the Brewski sisters, from "The 13 Ghosts Of Scooby-Doo."

1. They're a trio, and as Vincent Van Ghoul puts it, they can barely get their brooms to fly.

2. Marcella, one of the thirteen ghosts, brings them a spellbook, and orders them to recite Spell 13 in order to free her.

3. Though they're female, they're clearly modeled after the Three Stooges.

Correct--except they're actually called the Brewski Sisters. To be exact, the Moe one is named Wanda, the Larry one is Ernestine, and the Curly one (who is absolutely adorable) is called Hilda.
This is one of the episodes of the Thirteen Ghosts of Scooby Doo that I remembered probably the most from my childhood--it's a good one too.

Thanks, Glowworm. All fixed up. Now on to the next one, whom I've wanted to post for quite a while:

1. I'm one of many criminals from a show about a crimefighting cat and mouse.

2. My crimes include kidnapping a young brat, impersonating a stage actor who's impersonating me, (!), and robbing a wax museum where I wind up wax figures to go after the heroes.

3. I have a rather self-explanatory name, and share it with a classic Janet Jackson song.

I really thought the diehard fans would know this one. These are the last three clues:

4. Befitting what I am, I also figure prominently in a traditionally unlucky day.

5. I'm modeled on a great leading man whose films include "His Girl Friday" and "Notorious."

6. I'm literally a cat burglar.

Forgive me, I chased the problem from the wrong end. I looked up Janet Jackson's discography, and found "Black Cat," but couldn't connect that name to a cartoon character, only the Marvel Comics villainess. I should have attacked the problem the good side: Courageous Cat and Minute Mouse thwart a shifty burglar dubbed the Black Cat. Created by the same Bob Kane that gave us Batman and Robin; he was trying the vigilante duo along Lighter And Softer avenues.

OUB, you nailed it. As for the rest of the clues, he kidnapped bratty Melvin Vanderbort, impersonated Fred Footlight, who was ironically portraying him in a stage play, in order to steal the lead actress's necklace, and also went after jewels at the wax museum. He was modeled after Cary Grant, so they say.

The ball is once again in your court. Good job.

That's actually really funny because I found the right series--but didn't know of any songs of Joplin that sounded like one of the villains.

That's cuz I mentioned Janet Jackson, not Janis Joplin.

I REALLY wasn't paying enough attention last night.

Yahoo, now I have a chance to right a wrong that's been my albatross for a while. Here goes:

1) This character appeared in a regularly televised animated series that's no longer in production by the original studio.

2) The partner of this character has already been tapped and identified as a Mystery Character, so this character is the as-yet-unmentioned close associate.

3) This character takes a back seat to nobody; that'd be his partner. This fellow is in the driver's seat, because he's just that good at it.

I have a pretty good idea, but let's see if someone else gets it first.

Well, seeing as how no one figured it out, I'll supply the answer. It's Karate, from "Batfink."

1. "Batfink" ceased production in 1967, after 100 episodes.

2. I myself posted Batfink as a mystery cartoon character.

3. Karate drives the Batillac, just like Kato drove the Black Beauty.

Correct-amundo, this is Karate, from the Hal Seeger series. Karate acts as chauffeur as well as sidekick to the heroic Batfink; perhaps it's difficult to operate a motor vehicle while sporting steel batwings. Time to add another +1 to EmeraldIsle's total (341) and accede control of the board.

Thanks, OUB. Now here's one that's really and truly gone untapped:

1. My animated series is spun off from a live action film released the year before.

2. Like my live action counterpart, I struggle with my lycanthropy.

3. In fact, everyone in my family is just like me.

Ooh, I know who this is, and he's mightily deserving of the recognition, mostly because of his live-action actor. But I don't want to be hoggish, so I'll sit quietly and give someone else a chance.

I got an inkling on who it is--but I'm a bit tired tonight and have work tomorrow morning.

I believe this is Scott Howard, from Teen Wolf.