This movie or possibly TV episode (I saw it on TV) was set during the Cold War. The main character was a lady who could stop time for about 15 minutes or so.
There are a bunch of relatively mundane things that happen while the Cold War tensions keep rising in the background. In the final scene the main character leaves the store after having stopped time and sees a Soviet missile hanging in the air above the street (since time is stopped) about to impact the town (the missile still had all of the stages attached, for some reason)
Other details that I can (sort of) remember: it was set in a small town, I think during late 70s or 80s