After a tumultuous fall for several new fall dramas (soapy series “Revenge” has found ratings success while the much-hyped “Playboy Club” is already cancelled, and “Pan Am’s performance has been turbulent) two networks are rolling the dice on series based on fairytales. The shows, “Once Upon A Time” and “Grimm,” use similar source material in very different ways–and with mixed results.

“Once Upon A Time” creates a multifaceted and complex fantasy world–which is expected considering Adam Horowitz and Edward Kitsis, who wrote “Lost,” are penning the script. The story switches back and forth from an actual fairytale world to the small town of Storybrooke, Maine, where the fairytale characters live but are in the dark about their true identities.

This all threatens to change when 10-year-old Henry (Jared S. Gilmore) tracks down his birth mother Emma Swan (played by Jennifer Morrison from “House”). Armed with a thick book of fairytales, he knows the truth about the town’s inhabitants, and begs Emma to help him. As we find out in simultaneous flashbacks, Emma is in fact the daughter of Snow White and Prince Charming and is the “chosen one” the town has been waiting for.

Awash with love stories and soap-opera storylines, “Once Upon A Time” gets bogged down in the complicated mythology and jarring switches from fantasy world to real life. However, Morrison is compelling as Emma, a self-professed loner, and Lana Parrilla (as the evil queen and mayor of Storybrooke) is quietly menacing. As the series begins to delve into individual fairytales over the next few weeks, it could either get more interesting and addictive or complicated and difficult. Depending on how the next episodes turn out, it could become one of the best new dramas of the fall.

“Grimm,” on the other hand, is a much more straightforward adaptation of a fairytale. Instead of using actual fairytale characters, it draws on some elements of fairytales to build a new mythology. David Giuntoli stars as Nick Burnhardt, a police officer who discovers that he’s a Grimm, someone chosen to hunt the supernatural forces in the world.

“Grimm” is essentially a crime procedural with elements of “Buffy the Vampire Slayer” and “Supernatural” thrown in. The tone is dark, and despite a few efforts at buddy comedy between Burnhardt and his partner Hank Griffin (Russell Hornsby), the show remains quite serious–and therefore somewhat hard to take seriously.

In the pilot episode, references to fairytale classic “Little Red Riding Hood” are everywhere–little girls in red hoodies, preyed on by werewolf-like monsters called ‘blutbadden,’ waiting to be saved by the cops. In this sense, “Grimm” embraces old-school fairytale gender roles, where the innocent girls wait to be saved by the heroes, while “Once Upon A Time” features a more varied cast of heroes and villains, both male and female.

Still, for fans of crime shows, “Grimm” could grow into an enjoyable series that takes the best of crime procedurals while employing its own creative mythology. But before that happens, it will have to overcome its rather dull hero and tired gender roles.