Gifted with the ability to turn her flesh into crystal, the young girl known as Kole found refuge beneath the Arctic Circle. There, she discovered an exotic Underworld and befriended a gentle caveman known as Gnarrk. Only able to utter the phrase, "Gnarrk!", he and Kole share an unspoken bond.

When the Titans discovered this strange land during a battle with Dr. Light, the teen heroes became fast friends. Dr. Light attempted to use Kole's crystal form as a lens to increase his light-based powers exponentially. But the teen heroes banded together and it was "lights out" for Dr. Light once again.

After this adventure, Robin made both Kole and Gnarrk honorary Titans.

In the comics, Gnarrk was romantically linked to the psychic Titan known as Lilith. In the animated series, Kole takes Lilith's place as Gnarrk's special friend.
In the comics, the Titans named the caveman after the only word he repeated over and over: "Gnarrk!"

Producer Glen Murakami on Gnarrk: "We've gotten a lot of demand for Jericho and I've always wanted to find a story for Gnarrk, [..] We enjoy putting out own spin on the characters from the comics. A lot of these characters may not seem like standouts, but we find ways to make them cool and interesting."

Gnarrk first appeared in TEEN TITANS #32-33 [1971]. A gentle Caveman out of his own time, Gnarrk bonded with the Titan, Lilith Clay. Gnarrk appeared in TEEN TITANS #39 and #50-52, where it was revealed he was engaged to Lilith. In TALES OF THE TEEN TITANS #50 [1984], Lilith informed the Titans that Gnarrk died under mysterious circumstances. Gnarrk's story was revised and retold in NEW TITANS #56 [1989].

Kole
Calling All Titans
Titans Together

Dee Bradley Baker as Gnarrk