Rally your undersea friends! Aquaman (search), the world's most misunderstood superhero, is suddenly a big fish in Hollywood.

As the King of Atlantis, Aquaman's superpowers add up to having the ability to talk to marine life, breath underwater, swim really fast and wear a scaly orange and green costume.

Thursday night, he pays a visit to young Clark Kent on the WB's "Smallville" (search) and has been at the heart of this season's edition of HBO's "Entourage." (search)

Also, like most of the DC comic book characters, he is slated to be retooled over the next year as part of an ongoing story called "Infinite Crisis." (search)

Along the way, the character is getting more, uh, depth.

"We like to call him the much maligned Aquaman," "Smallville" creator Alfred Gough told The Post. "He always seems to get a bad rap for some reason."

When Aquaman initially came up as a possible guest star at the "Smallville" writers meeting, "at first we laughed," Gough says.

But the show's producers figured out a way to work Aquaman into the series in order to teach Clark Kent an important life lesson and set the stage for their later working relationship as members of the Justice League (search) -- a team of DC's most popular superheroes, chronicled in comic books for decades and more recently on the Cartoon Network show.

On "Smallville," Aquaman is a marine biology student and environmental activist from the University of Miami (the school's colors are, ahem, orange and green), who travels to Kansas to deal with Lex Luthor, who is testing a new sonar weapon in a lake near Smallville.

"The message he has for Clark Kent is that he should think globally, not locally," Gough says. "He shows Clark that he needs to wake up and realize that there's a bigger world out there than just Smallville and Metropolis and you have to use your powers to stop people from doing bad things."

"Entourage" -- a show about a fictional young movie star named Vincent Chase and his friends -- has Chase playing the watery hero in what is supposed to a big budget "Aquaman" film by "Titanic" moviemaker James Cameron.

For a long time, Aquaman as a superhero has been seen as kind of a joke among Hollywood insiders and many comic fanatics, which is likely the reason why the comedy writers behind "Entourage" chose him as the centerpiece of the show this season.

Aquaman first appeared in DC's "More Fun Comics" in 1941, and has had several variations on his origin story. One from the 1960s tells of how his father was a lighthouse keeper and his mother was a mermaid.

A more complex and more widely accepted story tells of Aquaman being born as the crown prince of Atlantis who was abandoned by his parents because of his blond hair, which was seen by his people as a curse. At first he was raised by a dolphin and then by a lighthouse keeper who gave him his own name, Arthur Curry.

Most casual viewers, however, remember Aquaman from the 1970s cartoon "Superfriends," in which he rode around on a seahorse, called whales with telepathy and basically stood around, useless, on dry land.

But DC revamped the character later, making him a Conan-esque hero who commanded an army and sported a hook for a hand. That was the makeover used by Cartoon Network's "Justice League," which made him less a hero than a loose cannon with a bad attitude.

Aquaman's sudden and unlikely prominence has not gone unnoticed.

"Yes, I've noticed the sudden resurgence," says Jay Franco, a die-hard comic book fan and editor for the Science Fiction Book Club, a division of the Book of the Month Club. "I'm not sure what is on the horizon for this superhero from the sea, but he is definitely worth keeping an eye on."