* Don't try to deviate from the plot.
* Try to involve all the five senses of the reader. How did the surroundings of the kidnapper's house look? How did the dead body smell? What was the look on the dead body's face? What kind of wound killed him? etc. These kind of details add more effect to the story.
* Always look at your story from a reader's perspective and think what should I write that would make the reader more involved in the story. Then write that, but also beware of giving too much details as they tend to slow down the story.