The next morning, Marlowe wakes up feeling disgusted by women. It is raining yet again, and when Marlowe walks outside, he sees the gray Plymouth sedan that had been following him parked across the street.
When he gets to his office building, Marlowe confronts the man in the Plymouth and says if he has something to tell him, he can go up to his office. Marlowe then storms off to his office to find a check for $500 from General Sternwood.
Twenty minutes later, the buzzer rings and the little man from the Plymouth appears. We learn that his name is Harry Jones.
Jones claims to have information that he's willing to sell Marlowe for $200. Jones tells Marlowe that Mona didn't run off with Regan, but went into hiding so that everyone would think she had gone with Regan.
Okay if that wasn't already confusing enough, let's add more plot twists: Jones says that he got this information from Joe Brody. Jones and Brody both work for Puss Walgreen, and apparently Brody was investigating the Regan and Mona connection to see if he could make money off it. During his snooping, Brody saw Mona in a car with Mars' gunman, Lash Canino. Jones concludes that this has to mean that Canino must know something about Regan's whereabouts.
Now here's the kicker. Apparently, Agnes recently saw Mona by coincidence and knows where Mona's hideout is (we think Jones knows Agnes through Brody). Jones says that as soon as Marlowe hands over the money, he'll take him to Agnes. Don't worry if you're still confused, so are we. It's kind of the point.