Well, “two cam,” anyway.

iMovie makes this basic postproduction technique — cutting back and forth between two or more cameras shooting the same scene at the same time — anything but easy. A guy on YouTube tries to show a way to do it, but I didn’t find his video half as helpful as the written instructions he put in the comments. The instructions assume you have basic skills doing cutaways:

1. Drag the clip from Camera 1 (“clip 1”) into the Project area.
2. Trim the head and tail of that clip to precisely what you want to publish.
3. Drag the Camera 2 clip (“clip 2/overlay clip”) into the Project area, dropping it on top of and at the beginning of the first clip.
4. Choose “Cutaway.” This clip will lay overtop of clip 1.
5. Trim the head and tail of clip 2.
6. Drag it left or right until the audio is synched.
7. Once the audio between the two clips is synched, never drag the overlay clip again, or they’ll become unsynced.

As it stands, you only see the video from clip 2. Here’s how to cut between them:

1. In the Project area, click on the overlay clip to select it.
2. Point your mouse to position the red playhead at a time where you want to cut to clip 1.
3. With the overlay clip still selected, press Command-Shift-S on the keyboard. This is the Clip > Split Clip command. The overlay clip is now split in two.
4. Drag the beginning of the second overlay clip to the right. This opens a gap between the two overlay clips, revealing clip 1 beneath them.
5. Repeat steps 1 – 4 as often as needed to cut back to clip 1.
6. As long as you only shorten or lengthen an overlay clip and never drag it from its middle, which moves it, your audio will stay in sync.

When you’re done

1. Drop the volume of the overlay clip to 0.
2. Double-click the overlay clip and turn on the Cutaway Fade.

but best practice would be to use a third track, audio only, recorded at the same time as the two cameras, as your audio track.