Their banter slays me. Montgomery: [profiling the triple killer] The feds say he's a white male, twenty-five to forty-five years old. Castle: [under his breath, to Beckett] Could be me. Montgomery: With a dysfunctional relationship with his mother. Castle: [sotto] Still me. Montgomery: He has a menial, unimportant job. Beckett: [sotto, to Castle] Definitely you. Castle: Just for that, I base my next book on Esposito.