TV Castle - Season 6 Castle - Season 6 /10 by 0 users Details Casts Posters Images Title Castle - Season 6 Alternative Titles First Air Date Last Air Date 2021-03-31 Number of Episodes 1 Number of Seasons 1 Genres , Networks , Casts Plot Keywords , Episodes List Castle Season 6 :Episode 1 Episode 1 Episode 1 2021-03-31