In the novel At Bertram's Hotel, Inspector Campbell is a younger inspector at Scotland Yard, assigned to find the missing cleric.
Inspector Campbell is described as "an ambitious young man", and finds much of his work tedious. However, he copes with the duties appointed to him, and is fairly successful at doing them. He is also described as having "an excellent figure".
Inspector Campbell calls Chief Inspector Davy "Father" behind his back, as everyone else does, but is not senior enough to be able to do it to his face.
Inspector Campbell goes to Bertram's Hotel, as part of his investigation into the disappearance of Canon Pennyfather. Chief Inspector Davy goes with him, as he is interested in Bertram's Hotel.
When Davy wonders if Mr Humfries is the owner or the manager of Bertram's Hotel, Inspector Campbell offers to ask him. However, Davy tells him not to ask, but to find out quietly.
After Canon Pennyfather is found, and has returned home, Chief Inspector Davy and Inspector Campbell go to see him. Inspector Campbell becomes rather exasperated when Canon Pennyfather is unable to remember anything that would help them.