Mark Waters Director Freddie Highmore Jared, Simon Grace Actor Sarah Bolger Mallory Grace Actor Mary-Louise Parker Helen Grace Actor David Strathairn Arthur Spiderwick Actor Nick Nolte Mulgarath Voice Joan Plowright Aunt Lucinda Actor Seth Rogen Hogsqueal Voice Martin Short Thimbletack Voice Karey Kirkpatrick Screenwriter, Producer David Berenbaum Screenwriter John Sayles Screenwriter Julia Pistor Executive Producer Tony DiTerlizzi Executive Producer Holly Black Executive Producer Mark Canton Producer Larry J. Franco Producer Ellen Goldsmith-Vein Producer James Horner Original Music Caleb Deschanel Cinematographer Michael Kahn Film Editing Jim Bissell Production Design Joanna Johnston Costume Design Odette Gadoury Costume Design