Would you ever ask your partner, "What's the worst thing you've ever done?" Such is the starting point for not one but two new projects out this month. The first was A24's buzzy marital dramedy The Drama . The second is Netflix’s docuseries Should I Marry a Murderer? , a three-part documentary directed by Josh Allott and streaming April 29, in which a woman recounts the horrors of learning about the murderous past of a man she nearly married.  Should I Marry a Murderer? centers on forensic pathologist Dr. Caroline Muirhead, who discovered that her fiancé, Alexander "Sandy" McKellar, took another man's life only a few years before meeting her. The true-crime story takes place in Scotland, where Glasgow -based Muirhead recounts how McKellar swept her off her feet over the course of a five-week whirlwind romance.…