An original character for the show, Frank is a mutated Venus flytrap brought to life by Poison Ivy and given the ability to speak (in the voice of J.B. Smoove, no less) and move around on his own (within the confines of a flower pot, that is). Though not technically a part of Harley's crew, Frank is very much a series regular, as well as Ivy's roommate. That said, he's not a very good roommate, since we discover he ate the kid she hired to come water her other plants while she was away at Arkham. A wisecracking, pot-smoking, free-loving guy who loves to get involved in everyone else's drama, Frank has quickly become a fan favorite, to the point where he jokes about having "tested well" when he breaks the fourth wall as a framing device in an episode of Season 2.
In Season 3, however, he becomes an integral part of the plot, as he is captured by none other than Bruce Wayne, who reverse-engineers Frank's DNA in a misguided attempt to bring his parents back from the dead. This short-sighted plan ends up accidentally initiating an ever-so-brief zombie apocalypse, which Frank assists in dealing with. After being juiced up via Ivy's connection to a mysterious force called the Green, he starts to morph and develop powers of his own. Despite his robust screen time compared to significantly better-known characters, Frank's humor is largely limited to snarky remarks at others' expense. Funny, but occasionally grating.
