Arlington Road (1999)

Hmm, I probably shouldn't have picked two movies in a row in which the FBI doesn't look so good. And it's not like I couldn't tell as much from the Netflix description. Well, at least this time, the agents make honest mistakes, albeit without apology. Also, their role is small enough to omit from the first paragraph of my summary.

In a Virginia town near D.C., Michael (Jeff Bridges) finds fourth-grader Brady Lang (Mason Gamble) badly hurt from a firework mishap. After reaching a hospital in time, he realizes that he hardly knows the Langs despite living across the street and having a son about the same age as Brady, Grant (Spencer Treat Clark). The grateful Lang parents, Oliver (Tim Robbins) and Cheryl (Joan Cusack), seem eager to befriend Michael and his girlfriend, Brooke (Hope Davis). But before long, Michael notes something fishy, and further investigation indicates Oliver's dishonesty. Could he be, y'know, the sort of criminal who can easily inspire a son to experiment with explosives?