Flashbacks have long been a common tool for filmmakers to show the audience information or events that happened before the film’s beginning. One classic example of such is in Michael Curtiz’s 1942 film Casablanca. Approximately in the middle of the film, Rick Blaine (Humphrey Bogart) has a flashback recounting his time with his old flame Isla (Ingrid Bergman) in Paris, after they unexpectedly meet up again in Casablanca.
The flashback begins in present-day Casablanca, with Rick getting drunk at his bar, with Sam (Dooley Wilson) playing Rick and Isla’s favorite song from their days together. Throughout the “pre-flashback”, the camera is pushing closer and closer to Rick, ending with him filling up the entire frame gazing off into the distance. Then, the scene transitions with a ripple dissolve, into a shot of Paris’ Arc de Triomphe, before again dissolving into a shot of Rick and Isla driving, smiling, with the Arc behind them. The audience immediately recognizes that this is a flashback of their time together in Paris, which was only hinted at before. The flashback continues with a series of short scenes of their time in Paris, with several dissolve transitions scattered throughout to show the passage of time. The flashback ends with another ripple dissolve back to the shot of Rick sitting in his bar, with Sam finishing the song.
This sequence raised a few questions for me. Firstly, why is the ripple dissolve transition so naturally associated with a flashback? When people think of their past, their memories do not dissolve, nor do they ripple, so how do audiences naturally realize that they are watching a flashback, as opposed to the next chronological scene in the film? Also, how do dissolves show the passage of time between shots? Can a similar effect be achieved with a different transition? How different would the flashback’s effect be if instead of dissolves (rippled or not), hard cuts were used? Lastly, how is music and sound employed to emphasize flashback? In this example, the song was shown to “bring Rick back to the past”. Would the scene play differently if there was no song playing in the background?