Underworld Friends should be a Dealbreaker

The trend that I found the strangest in the first half of Part 1 of The Stranger was Monsieur Meursault's lack of any sort of strong feelings to events that evoked powerful emotions for the reader. This character trait is best exemplified by Monsieur Meursault's dinner with his neighbor Raymond Sintes. Sintes vividly describes his plot to "punish" his mistress for cheating on him, including conversations he had with his "underworld friends" (31). Sintes finally decides to write a letter, with the help of his new pal Monsieur Meursault, to seduce her, and then throw her out "at the last minute" (32). To a normal person, and I assume I fall under this category, being witness to the birth of this barbaric revenge plot would be reason enough for me to do more than calmly drink wine and apathetically agree to a friendship.

This indifference towards the suffering of Sinte's mistress could be a coping mechanism for Monsieur Meursault, as he had just attended his mother's funeral, but I do not think that is the case. Monsieur Meursault did not know the age of his mother, nor the exact day she died, and he did not seem overly upset by the whole funeral process. 

Overall, our protagonist's apparent disconnect from the world around him gave the otherwise straightforward plot of chapters 1-3 an unshakable "there is something wrong here" feeling. The introduction of Sintes right at the end of chapter three enhances this tone by depicting Monsieur Meursault as complicit to  the destructive plot of one of his disturbing neighbors without showing any emotion.