Again, I’m looking at Carolyn Wheat’s list of 16 differences between mystery and suspense. You can find this list in Wheat’s book HOW TO WRITE KILLER FICTION. It’s also reprinted in T. Macdonald Skillman’s book WRITING THE THRILLER.
Difference number nine: In a mystery, information is withheld. In suspense novels, information is provided.
Mysteries always involve clues. Given all at once, the fun’s over. So the good mystery writer withholds the clues and dispenses them one by one over a period of time. Suspects lie. Witnesses flee. Crime labs take time to analyze clues and spit out results. Some clues turn out to be non-clues, or red herrings. Other clues are hidden in plain sight. Eventually, enough clues have been parceled out so the reader and the protagonist can solve the crime.
In suspense, the information is provided to elicit an emotional response. Think of JAWS. The viewer knows the shark is in the water. The viewer knows the young swimmer is clueless about the shark’s presence. Providing this information leaves the viewer feeling anxious for the health and well-being of the swimmer.
Another example is the book CARRIE by Stephen King. The reader knows Carrie has the power to avenge her humiliation. We also know that antagonists Chris and Billy are planning to humiliate Carrie at the prom. The information about Carrie’s powers, the events leading up to the prom, the prom, and the aftermath are all provided to give the reader a powerful emotional response. That’s suspense.
For what it’s worth.