Cocteau filmed this in reverse motion, making it appear on screen as if the flower comes back to life, with petals rejoining the stem.
By the time of Le Testament d'Orphée, use of reverse action was endemic in Cocteau's work, with more than one critic declaring it so overused as to be an embarrassing personal tic.
[1][7] The Christopher Nolan film Tenet (2020) heavily utilizes dramatic action sequences involving characters and objects that are time-reversed compared to the rest of the world.
[8] A similar approach may be taken also as a safety precaution, such as when a vehicle is required to stop from speed immediately in front of an object, as it can instead be started at the finish position and reversed;[9] for example, this trick can be seen in the Tomorrow Never Dies scene where James Bond pilots a life-sized remote-controlled car, stopping it mere centimetres in front of himself and Q.
The first is not an in-camera effect, but is achieved by printing the film backwards in an optical printer, starting from the final frame and working to the initial one.
(This requires a true optical effect, since simply playing the film in reverse when exposing it onto a new negative causes it to come out upside down.
Fourth, it can cause subsequent processing difficulties for the negative, because the registration pins will be engaging the film perforations on their opposite sides to normal.