New books with leading detective – this may be qualified as “noir” (5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

definition: reference to Pinot noir wine grapes (with “noir” distinguishing these e.g. from Pinot grigio grapes) N (New) + OT (Old Testament, “books”), with PI (Private Investigator, “detective” in front/”leading”