At Madison Park, John talks to an artist who gives lessons in the park every Monday, Wednesday, and Friday. Frank says that they're having trouble getting witnesses to the clandestine meetings. John spots some of the students' paintings, and they all feature a figure that looks like the P.I. meeting with a guy in a black duster. Frank asks the teacher when they were painted, and the teacher confirms that it was the previous Wednesday. Frank says that it's hard to get a good luck at Black Duster in any of the paintings. John points out that Black Duster seems to be using sign language, and wonders what he's saying. Frank doesn't believe that the P.I. would have any reason to know sign language. Frank and John walk off, and we see that Black Duster was watching them the whole time.

Back at the station, Frank reports that the P.I.'s grandmother recently went deaf, so he took a sign language class. Lt. Bosslady walks up and introduces an officer who knows sign language. She and John talk to each other in sign language for a minute, and then she says that she's on it, and leaves. I have to say, John's sign language sucks. He is way too emphatic and slow with his gestures. John explains that he got an approximate height and weight on Black Duster from the paintings, and that there are three hearing-impaired supply stores in Seacouver. John sent the officer to check with the owners and see if any of them could ID Black Duster. Frank says he'll call some hearing specialists to see if they can help. Lt. Bosslady asks John what he's not telling them, and who would be so desperate to reach him. John says he'd tell her if he knew.

Stella! All of my favorite tertiary characters are on this week. John explains to her that the sign language officer got a list of seven possibilities for Black Duster, and he's cross-referencing it with the phone company's records on owners of TTY units. Stella points out that hacking into the phone company's records is illegal. John tells her to call the cops. Stella picks out two names that fit the criteria and reads them out to John. One name is Charles Giteau, and John realizes that it's the name of the guy who assassinated President James Garfield. Stella does a reverse trace on the phone number and gets an address. John says that it's a transient hotel on Beacon Hill. Stella says that she'll call Frank, but John stops her. Stella says that she has to, and John promises to grab Frank on the way out.