Seconding Broadchurch, it’s incredible. Big Little Lies too. Poker Face arguably counts, with its Columbo-esque “just one more thing” motif. And The Flight Attendant gave me a lot more respect for Kaley Cuoco (of Big Bang Theory fame), though it’s also got some (darkly) comedic elements. Naturally, do a cursory search for all of these before passing them along: I enjoyed them, but idk what your grandparents are like…