"The Mummy's Heart" by Norman Partridge

This starts like your average horror story:  Two young brothers and a friend, trick-or-treating in 1963, run into Charlie Steiner, a twenty-three-year-old dressed like a mummy--better than your average costume, made worse by his own modifications:  lopping off a few of his own fingers and tongue.  He's got a young girl tied up and throw's her into the lake.

The cops get the guy, but the narrator's brother is dead and the girl has disappeared.  If the tale had ended here, the story would have been competent but forgettable.

But it keeps going.  We wonder if our narrator has lost his wits.  Was he imagining this all?

Our narrator goes to Vietnam, returns to be a cop in town.  But then a similar scenario plays out:  A biker gang is herding a young woman into the lake using flares. They have a shootout, and this time the narrator saves the girl.  Or does he?

I like a good, brief philosophical opening, but this one goes on too long.  Maybe skip it and come back to it after reading the tale through.  There are some open-ended, impossible-to-resolve aspects that some readers may enjoy speculating about:  Is there something in the lake?

Definitely check this one out.  This made me look for more of Partridge's work.  Most recently he's appeared in Nightmare magazine: "Bloody Mary".