VIDEO: Sneak Peek - 'The G.D.S.' Episode of ABC's CASTLE

On the next episode of ABC's CASTLE titled "The G.D.S." - Castle returns to the City of Angels in search of answers about his missing time. But things take a deadly turn when he’s recruited by the legendary Greatest Detective Society to help solve a murde.

The episode airs Monday, March 7th on ABC. Summer Glau guest stars as Kendall Frost, a heady private detective in Los Angeles who competes with Castle to try solving the murder, plus Gerald McRaney guest stars as Mason Wood, the head of the Greatest Detective Society. Get a sneak peek below!

Richard Castle — the devastatingly handsome and fun-loving mystery novelist — first connected with the NYPD when he helped solve a series of murders ripped from the pages of his famous Derek Storm novels. Suffering from writer’s block, Castle found a new muse in the beautiful and intelligent NYPD Detective Kate Beckett. Using his friendship with the mayor to weasel his way into shadowing her, their partnership inspired Castle to write a new series of novels, Nikki Heat. Teaming Castle’s writer intuition and Beckett’s creative detective work, they’ve spent seven years solving homicides in New York, including the murder that started it all, Beckett’s mother. And, of course, reluctantly falling in love.

“Castle” stars Nathan Fillion as Richard Castle, Stana Katic as NYPD Detective Kate Beckett, Tamala Jones as Medical Examiner Lanie Parish, Jon Huertas as NYPD Detective Javier Esposito, Seamus Dever as NYPD Detective Kevin Ryan, Molly Quinn as Alexis Castle with Susan Sullivan as Martha Rodgers. For Season 8, Toks Olagundoye (“The Neighbors”) joins the series as Hayley, a quick-witted, free-spirited, former Scotland Yard police officer who works as a security specialist and is not afraid to cross lines to get things done.