Castle Series Finale: 6 Burning Questions That Went Unanswered

Last night, ABC's Castle wrapped up its eight-season run with a final scene that saw the beloved Caskett seven years in the future, living with three children and a lot of books.

[...] while we know how the journey came to an end for Castle and Beckett, there are still some hanging plot threads that remained a mystery.

3 Why didn't Mason just take Castle and Beckett to his kill room after "saving" them in the first place?

[...] why couldn't he just kidnap the two of them after the shootout and give them the truth serum at the CIA building?

Tamala Jones, who plays Lanie Parish, was also reported to be leaving Castle after Season 8 even if the show had been renewed, but she only appeared briefly in the final minutes of the finale.