As Jake and Larsen know only too well murder investigations involve painstaking work and the endless pursuit of tips. Next up for them is the girlfriend of one of the bus massacre victims, Gus Niles, who they now know had been trying to buy an automatic weapon of the type used in the massacre. But first they have to find her. They begin at her workplace, the San Francisco Art Institute, at 800 Chestnut on Russian Hill (map), pictured here in a recent photo.
Larsen looks down through a window to an artist's model reclining languidly in the studio down below.
Then ... As he mutters disgustedly about the, er, corpulent sight a clue to where this was comes from the window reflection; he must be looking in from outside the building and there's a concrete roof above, unusually angled up rather than down.
... and Now, this outside space is on the upstairs deck of the Institute but has since been enclosed to create a Digital Media Lab. That exterior window, above, now hides behind the wall, below, and the concrete roof and beams have been refinished and painted.
... and Now, in this view of the Digital Media Lab, added since the movie was filmed, the reverse angle of the original roof overhang now makes sense - an architectural feature.
Then ... Larsen turns and looks across to Jake quizzing a couple of students about the whereabouts of Niles' girlfriend... that's Alcatraz and Angel Island in the distance. The window wall on the left is the same one through which Larsen looked down to the studio.
... and Now, the matching view is blocked by the media lab occupying this spot...
... and Now ... so we have to step outside to see the view as it looks today. The wall of the building, the Institute's cafeteria, incorporates projecting table tops, one of which the students were sitting on in the scene above.
Then ... They find she hadn't shown up for work that day so they head out the main entrance to try where she lives.
... and Now ... the same solid wooden doors are still in use.
Then ... She lives on Telegraph Hill - up there on the horizon - so they turn east down Chestnut Street.
... and Now, cypresses hug the front of the Institute and the sidewalk trees, pollarded every winter, have filled out after an extra 40 years of growth.