Stupidity: Of course, it's a movie with a heavy comedic tone and it's a rather cathartic scene, but still it's worth noting that Benoit Blanc had no way to know that making the whole HOUSE (full of glass shrapnel, too) explode wouldn't gravely injure or kill anyone. What a ruthless fellow.
Suggested correction: The scene at point 2:06:02 suggests the opposite. Blanc knew the house would explode violently, hoped everyone would get injured, and sat watching it while helping himself and Derol to a cigar. Bron was guilty of two counts of first-degree murder. The remainder were accessories to the crime, having already pledged to perjure themselves. Their sentence would be death if it were not for their destruction of evidence. So, all Blanc needed was a sense of justice, not ruthlessness.
Helen, the innocent sister of the original murder, is in the building too. I wouldn't want to say that he hoped *everyone* would get injured, just the bad guys but that's the point. It's simply a case of an absurd decision that puts to mortal risk everyone but has no negative consequences "because movie."
Yes, exactly, "because movie." You see, this site's "Stupidity" tag is for the kind of stupidity that a movie _commits_, not those that a movie _shows_. Characters can be desperate, crazy, angry, hopeless, and yes, stupid.