Experiment In Terror - Popcorn at the Country Club
A police paid informant, Popcorn by nickname because he always seems to have a bag of it in his hand, has information on Red Lynch but he slyly implies he may sell it to the press first. Ripley sets up a plan to appeal to his conscience ...
Then ... Popcorn (Ned Glass) is first seen in a silent movie theater watching comedy clips.
CitySleuth doesn't know if this was filmed at a real theater or a studio set - can anyone out there enlighten him? But he can tell you who the comedians on-screen are, thanks to John Bengtson, who hosts a well-researched silent movie website. Per John, the incompetents on the right (below) are Mack Sennett's Keystone Kops in a clip which can be seen here. The man on the left is Billy Bevan, possibly from the short 'Be Reasonable', being chased by those same hapless Kops.
Then ... Ripley asks Popcorn to meet him at the Marin Town and Country Club, a short drive north of San Francisco in Fairfax, also featured earlier in the movie (go there for location and details). He spots Popcorn from the snack bar near the ping-pong tables.
... and Now, those buildings in the background (they were public toilets), are still there, unused since the club closed down in 1972.
... a vintage photo ... in this undated photo we see the snack bar as it must have been when Ripley was there.
... and Now, what's left of the structure is all boarded up.
Then ... They meet up and walk towards a couple of gabled cabins. As they talk, Ripley points in the direction of the swimming pool.
... and Now, the same cabins, next to the pool fence, are still recognizable.
Then ... He points out Kelly and Toby chatting alongside the pool and tells Popcorn that if he sells his information to the press that one or both of them may be dead by the weekend. Having planted the thought he then leaves Popcorn to mull it over.
... and Now, forty years without grounds maintenance has led to this matching view. You can still see the basketball hoop backboard, now rusted, in the background.
The strategy works - Popcorn takes the police to a public telephone in a seedy part of town (CitySleuth thinks this was a studio location) where Red Lynch has been calling an accomplice nightly about Kelly Sherwood. They watch and wait for the next call ...
... but the accomplice spots them and is killed in the ensuing exchange of gunshots - unfortunately Popcorn is caught in the crossfire, collateral damage, never to snack again.