Crosscutting is a technique used in film editing that temporally relates shots. Crosscutting is used to show multiple, usually simultaneous, events by alternating shots from each event.
Crosscutting is best understood when explained with a diagram (sorry for the bad ASCII art). The example below shows three people: A, B and C. Person A is trying to distract person B, and the two of them are inside a building. Person C is outside, trying to sneak past a window that person B had been looking through. Shots from each event are offset from each other, for clarity.
+------------------------------------+
| |
| |
| |
| _____________ _____ |
| O | O O | | | |
|/ \ | / \ / \ | | | |
||C| |__|A|_|B|__| | o| |
|| | | | |
+------------------------------------+
Shot 1: This establishing shot shows the general setup for the scenes. Person A and B are inside, and person C wants to sneak past the window and go through the door.
+------------------------------------+
| |
| ___ ___ |
| / \ / \ |
| | o o /// | | |
| @ \| \__) |@ | |
| \__o/ / / \___/ |
| / \/ / / \ |
| | A / / B | |
+------------------------------------+
Shot 2: Now we cut to the interior of the building, where we see person A trying to distract person B.
+------------------------------------+
| |
| |
| |
| _____________ _____ |
| | O O | O | | |
| | / \ / \ |/ \ | | |
| |__|A|_|B|__||C| | o| |
| | | | | |
+------------------------------------+
Shot 3: We return to the first thread of action, which is person C trying to sneak past the window outside.
+------------------------------------+
| |
| ___ ___ |
| / \ / \ |
| | | o o | |
| | @| |/ @ |
| \___/ \o__/ |
| / \ / \ |
| | A \ / B | |
+------------------------------------+
Shot 4: Now we see person B speaking to person A, back inside the building. Note that the interior event is shot using a shot/reverse-shot pattern, another editing technique.
+------------------------------------+
| |
| |
| |
| _____________ _____ |
| | O O | | O |
| | / \ / \ | | / \ |
| |__|A|_|B|__| | |C| |
| | | | |
+------------------------------------+
Shot 5: Another cut back to the action outside, where person C is opening the door.
+------------------------------------+
| |
| ___ ___ |
| / \ / \ |
| | o o | | |
| @ \| |@ | |
| \__o/ \___/ |
| / \ / \ |
| | A \ / B | |
+------------------------------------+
Shot 6: Back inside, where we see person A talking to person B.
+------------------------------------+
| |
| |
| |
| _____________ _____ |
| | O O | | O | |
| | / \ / \ | |/ \| |
| |__|A|_|B|__| ||C|| |
| || || |
+------------------------------------+
Shot 7: Back outside, person C has opened the door and is going into the building.
Both events, the conversation and the sneaking, occur simultaneously. Although crosscutting was used here, the filmmakers might have chosen to use a split screen to display both events at the same time. While crosscutting may seem more disorienting than split screening, it is by far the favored technique. Film spectators have little trouble interpreting crosscut events.
Crosscutting is a powerful editing tool that allows the spectator to have a nearly omniscient view of the entire film. By alternating shots of simultaneous events, spectators have knowledge of all the events, something which the characters do not have. While crosscutting can disrupt spatial relationships, but jumping from one event to another, this technique links them together in time. Also, crosscutting can imply a cause and effect relationship between events, which lessens disorientation.
Filmmakers often use crosscutting to heighten suspense. Each cut between events creates a mini-cliffhanger, which are resolved at the editor's discretion; editors may choose to leave one plot thread hanging by interleaving shots from other events, only to resolve the original thread at the end of the sequence.
Editors may also use crosscutting to emphasize a graphical or rhythmic theme. In graphical terms, an editor may choose to crosscut events to suggest parallels, shown by graphical matches. One of the finest examples of rhythmic crosscutting comes in Sergio Leone's The Good, The Bad, and The Ugly (Warning: Spoiler ahead): In the Mexican standoff at the end of the film, the duration of the shots become shorter and shorter, closer and closer, increasing the suspense of the gunfight.
We can take a concrete example of a standard crosscutting sequence from Everything2's favorite film, Fight Club. Warning: Minor spoilers ahead.
Around an hour and 11 minutes into the film, the members of Fight Club go on their first homework assignment: picking a fight with a total stranger and losing. There are three lines of action in the sequence: Guy with the car salesman (GCS), mechanic with the priest (MAP) and Bob with the bicycle messenger (BBM). Shots from these three events are crosscut in the following order (they are offset for clarity):
1. GCS
2. MAP
3. BBM
4. GCS
5. BBM
6. MAP
7. GCS
8. BBM
9. MAP
10. GCS
11. BBM
12. MAP
When you're watching the film, you're probably not aware of the editing at all. We're all so used to the technique of crosscutting that we take it for granted, and immediately and unconsciously understand the effect. We perceive all three events happening at the same time, even though each scene is chopped up.
Notes
David Bordwell and Kristin Thompson. Film Art: An Introduction, Sixth Edition. (New York: McGraw-Hill, 2001).
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