Logline: “When the dark secrets of a timid family man are about to be exposed by an anonymous source, he must take on dangerous assignments over the course of one night, in an attempt to save his marriage and family.” (39 words)

Overall, the logline describes a simple-sounding story. But as mentioned in previous reviews, parts which are vague and parts extraneous to the logline make it too long and weaken the overall logline.

Breakdown:
Protagonist: “a timid family man” —> This is okay. But I suggest a rewrite –? if the protagonist is religiously devout and thus strongly believes in the sanctity of marriage, for example, that could be expressed which makes any past actions which seem to go against his values have value and add more stakes.

Antagonist: “an anonymous source” —> This could be cut from the logline. It tells the reader nothing about the antagonist. Consider changing this to a more general statement.(Will include example at end of review)

Inciting incident: “When the dark secrets of a timid family man are about to be exposed by an anonymous source” —> The logline describes what appears to be the correct inciting incident, but this could be reworded. Also, ‘dark secrets’ is too vague.

Goal: “he must take on dangerous assignments over the course of one night, in an attempt to save his marriage and family” —> As mentioned by another member, “in an attempt to save his marriage and family” isn’t useful to this logline. The goal of the story is to prevent the exposure of his secrets.

An example, using elements from your logline:?After he receives an anonymous letter threatening to expose his illicit affair, a devout Christian cop must impede a murder investigation to protect his secret. (25 words, 166 characters)