Castle Season 7 Episode 20 Sneak Peek # 1 “Sleeper” Castle with Dr Burke and Chuck Norris in dreams Castle 7x20 Promo, “Sleeper” – A mysterious recurring dream drives Castle and Beckett to seek answers about the two-month period when he went missing. But their search for the truth has deadly consequences,on“Castle,” MONDAY, APRIL 20 (10:01-11:00 p.m., ET) on the ABC Television Network. “Sleeper” was written by David Amann and directed by Paul Holahan.