The Sketching Detective and the Bluffton Murders

Late one night Fiona and Jack, after a long day in the sun, were sound asleep when they were suddenly awakened by wild, frightening, almost bloodcurdling screams. Although Fiona is much braver than Jack, she, on this occasion, was very much alarmed while Jack was very calm. He had heard those screams before. They were made by a barred owl also frequently referred to as a hoot owl.
The owl seemed to scream these words, "Whoooooo cooooooks for youuuuuu? Whoooooo cooooooks for youuuuuu?" According to an old wives' tale common to the South Carolina coastal area, this owl arrives screaming in the neighborhood on the night when someone has just been murdered in the vicinity. The fact that on one particular night the owl arrives screaming its best when no one seems to have been murdered nearby provides a very important clue that helps our investigators identify the killer.