Phone calls and IntercutsIntercuts are when we switch back and forth between two or more scenes quickly and repetitively. Most often we see intercuts when characters are speaking on the phone and we jump back and forth between them.
Sometimes intercuts happen with scenes that are related by time, but not dialogue, like when we see someone dismantling a bomb and cut back and forth between that person and the people in a safe place who check their watches, waiting for him. Intercuts have also been used in time travel situations.
All you want to do is start the intercut and let the director decide how to do it. Like this:
EXT. HWY. 57, PHONE BOOTH - DAYJessie runs into the booth and quickly dials a number. Intercut with...INT. MULDOON'S OFFICE - DAYMuldoon grabs the phone almost before it rings.MULDOON Yea, what' up?JESSIE He's here! Hurry!Often the intercut will end at the next Scene Heading. If you want the intercutting to end in one of the locations you've been using, just reuse that Scene Heading. So, to do that by continuing the above scene, we get:
MULDOON We got you, Jess. Just leave the phone off the hook and hide out till we get there.JESSIE Okay. Please hurry!Jessie drops the phone so the receiver dangles. He runs away.MULDOON (to his assistant) Get a trace on this. Fast!EXT. HWY. 57, PHONE BOOTH - DAYA gloved hand hangs up the phone.So you can see that when the Action refers to Jessie dropping the phone, it's obvious that the director will have to cut to that location. But we really emphasize the return to the phone booth by adding the Hwy. 57 Scene Heading.
Realize, of course that you can have a phone conversation without intercutting. The scene takes place in one location and the person on the other end of the phone talks in voice-over.