Mike Dashwood is investigating pilfering from a building site. Foreman is not cooperative. Roache gets him to interview a lad about a stolen moped. Father hits Mike and then follows him as he goes to met the foreman. Foreman tells Mike not to come onto the site again after handing over a list of names. Mike is beaten unconscious and list is missing. June is talking to Melvin about taking her Sergeant's exams. She tells two boys off for riding bikes on pavement. June and Melvin respond to call and find Mike.
