A scene can lack tension for various reasons. In this case, it was because none of the characters was allowed to react to the discomfiture of a main character when someone inadvertently reminds him he was away from his wife when she was dying of cancer. Actually, it may be more accurate to say everyone's reactions to the moment were subdued. It made the scene and the characters appear dull, one-dimensional.
|Conflict should be palpable|
In this case, the universal lack of response drained the life out of the scene. Yet, characters—I like to call them people—long to get out of their shells if we'll let them. We don't need permission to write the truth; it will set us writers and our characters free.
Tip: The fix in a case like this is to revise by re-visualizing, re-visioning the scene, if we can use those words as Natalie Goldberg did in Writing Down the Bones. Start with a clean sheet of paper or a new document, and close your eyes. Allow the scene to materialize, and watch each person respond. This will deepen the scene and broaden it. For more on this technique, see the post "Stephen King to the Rescue: Using Imagery to Bring a Story to Life." And see the August issue of The Writer, the magazine archive piece by Stephen King called, "Use Imagery to Bring Your Story to Life."