They were then introduced to the mysterious "Q" (a certain Mr Coates who claims to be a technical teacher) and the "Professor", who says she is Fiona Craig, PT chemistry, but is in fact in charge of "Forensics".
Themed around murder and mystery this unique whodunit induction process sees departments transformed from the likes of computing, home economics and religious and moral education into the Centre for Information Analysis, Sensory Investigation and the Spirit Guide, respectively, as primary pupils hone their investigative, research and learning skills to help solve mysteries and a murder.
Entitled "Skills, Thrills and Fun" (STF), the two-day induction process is intended to identify and fill in skills gaps, such as alphabetisation, decimal numbers, key words, listening, planning and reading. It also reinforces specialised terms such as contents, list and index.
The real Philip Graham explains: "The need to change the induction process has been emerging over a number of years. Skills gaps and a lack of uniformity in skills were emerging in the S1 population where pupils were struggling with tasks because they were assumed to have skills which were either not there or were not recognised by the pupils as being connected to the task - for example, the connection between alphabetical order and looking up the meaning of a French word in a French-English dictionary.
"A list of assumption skills was issued by school librarian Ian McCracken as a starting point and, using the S1 after-school homework club to research skills gaps, tasks were developed for volunteer pupils which both engaged the pupils and addressed the skills needs."
The result is Skills, Thrills and Fun which Mr Graham says is better than a mini school day from which they learn little or nothing. It also unleashes teachers' creativity and it is hoped to extend the project to P5 and P6 classes within three years.
The investigating groups are made up of pupils from different primaries who can get to know each other in advance of next session. Groups are chaperoned by S3 pupils, each wearing an "Investigation Support Team" T-shirt.
"These S3 pupils provide the basis for next session's S4 buddies. We want the S3s to lead on this project with the teachers taking a back seat," Mr Graham says. "We hope STF will become a recognised brand so that in a library session in S2, for example, we can say: 'Look back to your STF experience when we did alphabetisation and make use of the skills you learnt then.'
"It's a wide programme that all departments can make use of. It links to every subject and to the kinds of skills pupils need for all subjects and the kinds of skills they will need for life and work."
Fiona Craig says: "At first there was a wee bit of a panic about the idea but it's going smoothly and is getting the skills across well, while being great fun.
"It could certainly feed into everyday lessons and help link science to the world outside the school because all the kids can relate to police and crime dramas on television."
"Great fun" was the verdict of the investigating primary pupils and, as one budding detective put it, "not like hard work at all".
What will Agent Graham find with the metal detector the school has borrowed from Strathclyde Police? Will the Professor discover the true colour of the poisoned Smartie? Who are the men in the kidnapping video? And what happened at the last crime scene?
To quote Chief Inspector Taggart: "Therr's been a murrderr!" And my bet is - it was a teacher whodunit.