As revealed at the series' panel for Comic-Con International in San Diego, Syfy's adaptation of the Grant Morrison/Darick Robertson graphic novel Happy! has recast the title role of Happy the Horse; Patton Oswalt will take over for Bobby Moynihan (via Deadline). Moynihan voiced the character in the pilot.

The network’s official description for the series is as follows: “The series follows Nick Sax (Christopher Meloni, Law & Order: SVU) – an intoxicated, corrupt ex-cop turned hit man – who is adrift in a world of casual murder, soulless sex and betrayal. After a hit gone wrong, his inebriated life is forever changed by a tiny, relentlessly positive, imaginary blue winged horse named “Happy” (Patton Oswalt, Parks and Recreation).”

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Joining Meloni, Moynihan and villain Joseph Reitman in the series are Patrick Fischler (Lost, Mad Men), who is set to play Smoothie, Ritchie Coster (Blackhat) who is set to play Mr. Blue aka Leonardo Scaramucci, and actress Zabryna Guevara (Gotham), who will play the beleaguered single mom Amanda Hansen.

The pilot episode was written by Grant Morrison and Crank writer-director Brian Taylor, with Taylor also stepping behind the camera to direct. Morrison, Taylor and Meloni all serve as executive producers, along with Neal Moritz, Pavun Shetty and Toby Jaffe of Original Film, and showrunner Patrick Macmanus.