The bullet fired by Arthur Ashton (killed by Sgt. Joe Friday) traveled along the bottom of the shelf behind Joe Friday. It lodged in the wall after lifting the shelf leaving what appeared to be a carpenter's mark. The shelf fell back into place hiding the bullet from the vision of those searching for it, until Lt. Pierce Brooks moved the shelf finding the bullet.
Joe Friday appears in the perpetrator ("perp") end section. In his case it reports "Sgt. Joe Friday. Returned to duty."
Date: Wednesday, September 17
Working: Day Watch, Homicide
Boss: Captain Hugh Brown
Gannon: (to Friday) Nothing ever happens the easy way to you, does it?