O'Hara has signed the 'confession' for Grisby's fake murder believing that he can't be convicted because Grisby will have disappeared from view. No body, no conviction. They are ready to stage the murder but the event is bookmarked by two real murders.
Bannister's assistant Broome has overheard some of the plotting - concluding that Grisby is about to kill his boss - but when he threatens blackmail Grisby without hesitation pulls a gun and fires.
Then ... O'Hara, unaware of Broome's shooting, returns with Grisby to the Walhalla bar (at 201 Bridgeway in Sausalito, described previously here) and fires off a few shots to catch people's attention while Grisby slips away.
... and Now, the building is still there but has been widened and extended out closer to the boardwalk.
Then ... while O'Hara is attracting a startled crowd Grisby jumps unseen into a motor boat and heads past the anchored Circe towards the glittering San Francisco shore. Reader Wallace Berry has pointed out that this boat wasn't the Zaca (used for the Acapulco scenes), but a stand-in, the White Cloud.
... and Now, the same skyline, though far more developed, is as beautiful as ever - the Bay Bridge, as strings of pearls, only enhances the scene. A few skeletal remains are all that is left of the pier.
Then ... Grisby completes the crossing and arrives at a marina.
... and Now, this is the West Harbor in the San Francisco Marina district, in front of the St. Francis Yacht Club (map). Fort Mason is In the background at left and Russian Hill at right. (Incidentally, the 1951 movie The House On Telegraph Hill featured the same pier - see it here).
Then ... O'Hara phones Elsa only to reach the mortally wounded Broome whose gasping last words tell him Grisby is on his way to kill his law partner (Bannister), planning on pinning the murder on O'Hara. O'Hara frantically drives over the Golden Gate Bridge to Bannister's office in San Francisco.
... and Now, CitySleuth snapped this matching shot at the south end of the bridge from a location off limits to pedestrians (only cyclists can use this side) for which he was rebuked by the authorities. If you look carefully you can see the recent addition of a safety railing, elegantly done on each side, between the pedestrians/bikers and road traffic.
Then ... The camera pivots, following the car, and we see the Round House on the right, opened as a restaurant for passing motorists in 1938, one year after the bridge was inaugurated. In the distance just left of center is the dome of the Palace of Fine Arts and Coit Tower atop Telegraph Hill is discernible at far left.
... and Now, the Round House is still there, now a gift shop for the ubiquitous visitors.
Then ... O'Hara arrives at Bannister's office and finds the police are out front responding to yet another murder. But, surprise, it's Grisby who has been shot! The police find the confession on O'Hara and promptly arrest him.
Wouldn't you know it, this scene was filmed on the Columbia Ranch, the original back lot for Columbia Pictures, in Burbank (map). Below is an image from a 1949 Batman and Robin TV episode filmed at the ranch showing the same building, known as the Kirby Building. It was subsequently destroyed in a devastating 1974 fire but the ranch is still operational, now called the Warner Ranch.
Just to dot the i's, below is the Columbia Ranch layout as it was when the movie was filmed, with the Kirby Building corner shown arrowed. The two views above look across New York Street with Brownstone Street teeing in on the right. (CitySleuth is indebted to the excellent Columbia Ranch website for these images).
David and Petulia have sailed their yacht to Peru and we see them relaxing at a marina somewhere south of the border while a radio station chatters away in Spanish in the background.
Then ... But sombreroed locals and a few potted palms dotted about didn't fool CitySleuth. This scene was filmed at Kappas Marina in Sausalito (map), just north of San Francisco! Check out what appears to be a causeway at upper right and a mountain slope behind it in the composited panorama below.
... and Now, the causeway is Highway 101 crossing Richardson Bay and the mountain, fully revealed under clear skies, is Mount Tamalpais. The hills behind Sausalito are in the left background.
Then ... Here's an aerial photo of Kappas Marina taken in 1968, the year Petulia was filmed.
... and Now, compare it with the marina today, now called Richardson Bay Marina, as captured in the Google satellite view below. The marina has been renovated and expanded and a houseboat community, retaining the Kappas Marina name, has been built between it and the adjacent Highway 101.
Below deck, David is overcome with self-recrimination. "Only a crazy man can hit a woman ... or a coward". He commits never to do it again and Petulia, believing him or not, forgives him.
Walter Williams (Brian Donlevy), a hardnosed, successful businessman, lives in the Bayview Apartments with his wife Irene (Helen Walker), over whom he shamelessly fawns. The apartment shows up a number of times throughout the movie and the images have been aggregated for this post.
Then ... A visitor drives up a steep hill and turns into the apartment courtyard.
... and Now, the steep hill is Sacramento Street and the apartments are the Brocklebank Apartments at 1000 Mason Street (map), former home of San Francisco's iconic Herb Caen. Another famous resident of the Brocklebank was the enigmatic Madeleine in Alfred Hitchcock's masterpiece Vertigo (seen here). The Fairmont Hotel is on the right.
Then ... When the visitor enters the lobby, we wonder if this was filmed inside the Brocklebank?
... and Now, the answer, based on the real lobby below, is no. Evidently a studio set was used but some similarities are there - in particular, the corridor with four steps leading from the lobby. There was an elevator on the right in the movie set (above) but in real life the courtyard is on the other side of this wall.
Then ... Inside the Williams' apartment, the window view behind Walter is of the Bay Bridge where it meets Yerba Buena Island (map). This again was a studio set, using a photograph to represent the view.
... and Now, the east facing windows of the Brocklebank did indeed have a view of the bridge back then, before today's Financial District urban jungle blocked it, but the angle doesn't correspond to the movie view above. That photo was taken from further north, most likely from Coit Tower on Telegraph Hill, like the recent one below.
Then ... But when we are shown this view looking down to the courtyard from another of the apartment's windows, it's the real thing.
... and Now, the same view from ground level, unchanged in 60 years but for the lamp-posts. The building kitty-korner across Mason Street is the Pacific Union Club, also featured in Vertigo as Madeleine's husband's club (see it here).
... The Brocklebank Apartments today ... This fine 1926 building is testament to the days when class informed architectural design. It was designed, as too was the nearby Huntington Hotel, by the architects Weeks and Day.
Then ... Kelly drives to work, heads down a narrow alley, and pulls into her downtown garage.
... another look ... Below is another view of the alley seen later in the movie. Recognizing the building across the street at the end as the distinctive Hallidie Building at 130 Sutter Street led CitySleuth to the garage site, which as it turns out has since been built over. The 1962 San Francisco street directory revealed that it was the Lick Garage at 55 Lick Place, an alley between Post and Sutter.
... and Now, the garage and the alley were demolished in the early 1980s to make way for a shopping mall, the Crocker Galleria (map). The matching photo below was taken from where the garage would have been - the ground level is a few feet lower and the line of shops on the right side sit astride where the narrow alley, no more than 30 feet wide, used to run. The Hallidie Building, still there across Sutter Street, is currently hiding behind scaffolding.
A vintage photo ... This 1950 photograph showed the entrance to Lick Place at Sutter Street. The classy building on the left is the Hunter-Dulin Building at 111 Sutter. The alley side of this building is on the right in both of the 'Then' images above.
... and Now, the Hunter-Dulin Building is still there but the narrow alley and the two-storey building beyond it have been replaced by The Crocker Galleria.
Here's the 1962 Street Directory entry confirming the address and name of the garage.