Make the pause decision before anybody is interrupted
Ask whether the person who may leave wants to finish with the group. They may prefer everyone to continue, or they may want a shared stopping point. Do not wait until a work call arrives to decide whether the whole room should sit in silence.
Pick a format that fits the uncertainty
If the interruption could take five minutes or an hour, choose two separate episodes or a film everybody is willing to pause. Put an easy independent activity nearby for the others. A person might read while waiting without losing their place in the shared evening.
Use a clear restart cue
Set the remote where anyone can reach it and record the stopping point if the pause becomes long. If the person cannot return, decide whether to save the rest for them before starting it again.
For example, “If the call is under ten minutes, we will resume together. After that, we can play cards and keep the film for tomorrow.” Record the point where everyone stopped if the evening changes. When the person returns, tell them which plan was used without spoiling any scenes they have not seen.