The House on the Cliff (Unabridged‪)‬

In this early Hardy Boys book (the second to be published), the boys journey to a haunted house where a murder took place, and upon entering, hear a spine tingling shriek. At first they tuck their tails and go back outside, but then being the adventurous sleuths they are, they go back into the house to investigate. Why does everyone believe the house is haunted, and where did the scream come from?