Given that, it's fitting that the trailer for When A Stranger Calls ignores the rest of the movie and advertizes the opening alone. There's not a moment of the rest of the movie shown in the trailer and what's even funnier is that the trailer gives away every shock and surprise of the opening - we even see Kane opening the door to reveal Charles Durning! You'd think that'd have been a big issue at the time but no one seemed to mind. I know that as a kid, the trailer for When A Stranger Calls was perfect because there was no way I was going to get to see the movie anyhow so seeing a trailer that gave away all its best moments suited me fine.
The downside to that is that the trailer also completely traumatized me. I was a latch-key kid at the time and for weeks, whenever the phone rang after school I had one eye on the stairs to our second floor - just in case a shadow would appear on the wall and I'd hear foots on the steps. Looking back, I have to say I'm not even sure if we actually had a second line in the house at the time - and if that's the case, then this trailer had me not only jumping at shadows but had me imagining someone calling me on an imaginary phone. That's what I call getting me good. Well played, When A Stranger Calls, well played.
And here's a teaser for the UK release of the film that proves - years before Paranormal Activity - that you can never go wrong showing an audience losing their shit at a movie.