Editor's note: CNN Contributor Bob Greene is a bestselling author whose 25 books include "Late Edition: A Love Story" and "Once Upon a Town: The Miracle of the North Platte Canteen." His commentary on the Colorado shootings will appear on "CNN Newsroom" Saturday during the 3 p.m. (ET) hour.
(CNN) -- It is the implicit bargain every moviegoer makes.
You buy your ticket, you go into an auditorium full of people you don't know, you look toward the front of the room, the lights go down -- and in the darkness, you are safe.
On the screen in front of you, startling things may be going on: gunfights, automobile wrecks, romances suddenly turned dramatically ugly. You have willingly suspended disbelief; for two hours, you have voluntarily joined into the story looming so large in front of your eyes that you have pushed aside the fact that you are still just you sitting in a room in your town. The most dangerous things can be taking place in the front of that room, yet you are secure and protected. There is a cocoon that the moviegoing experience provides, and every time you step into a theater you are back inside of it.
Of all the haunting thoughts that have accompanied the tragedy this weekend in Aurora, Colorado, one of the hardest to shake is that of all the people who -- as they had always done at the movies -- were sitting in their seats in the minutes before the lights dimmed, staring straight ahead, and hoping that something good will come of the night.
That word -- hope -- is one that is forever attached to the act of going to the movies. Roger Ebert, a friend of 40 years, once told me that no matter how many movies he has seen, he always enters a theater hoping that by the time he emerges into the light of the mundane workaday world something will have happened on the screen at the front of the theater to make him glad that he has spent the time. If you don't walk into a movie theater hoping, then there is no reason to make the trip.
So the thought of those men and women in Colorado leaving their homes Thursday evening, the thought of them making their way down the aisle and choosing their seats and, with anticipation of something pleasurable, of something memorable, settling in and casting their eyes upon the screen. . . .
The thought of that is heartbreaking precisely because the rest of us can all imagine it. We've all been there.
The one thing you would never expect -- that someone with murder in his heart will be looking back toward all the eyes, will be standing in the one place no one is supposed to stand, will be peering away from the screen and into that roomful of hopeful faces -- is what makes the thought of what happened almost unbearable.
What is the phrase that every parent has told a nervous child when things on the screen become a little scary?
"It's only a movie."
What is the variation of that phrase that Hollywood studios have used to entice ticket buyers to horror films?
"You'll have to keep telling yourself, 'It's only a movie.'"
No one is supposed to intrude upon the space between the audience and the screen. To do so would be to shatter the illusion.
It was shattered in unthinkable ways in Colorado this week. There is an old Life magazine photo, taken to illustrate the magic of the movies, that is so glorious because it shows the one scene that moviegoers never witness. The photographer positioned his camera at the front of a movie theater and snapped the shutter as all of the people in the seats are gazing upward at the story on the screen. Their faces are bathed in the light from the movie. They are in the midst of a journey.
Going to the movies means turning yourself over, giving up control, opening yourself up to whatever may come next at the front of the room.
And that is so much a part of the sorrow of what happened in Colorado. For the families of those killed and maimed, the very thought of going to the movies will now eternally feel like a dagger to the soul. For the rest of us who read about it and hear about it and report on it, it is unlikely that those moments at the movies just after the lights are doused will soon feel the way they did before.
It is that implicit bargain:
We sit in the dark, in a room with people we know nothing about.
And then, when the lights come up again, all is calm and sedate. The world outside, the world we truly know, awaits our return.
A night at the movies is supposed to grant that promise, that happy ending.
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