Det. Murdoch investigates a series of deaths among members of a Toronto military regiment. All were in the same squad under the command of British Maj. Gregory Bole, on loan to train them in a new kind of warfare using what's called kommando tactics. When Murdoch learns that the men had signed a tontine agreement where the last man living would inherit all of the others investments, he thinks he's identified the killer, Matthew Larson who resigned from the regiment a few months before. It's not that simple however and when Murdoch learns that others in the squad are all hospitalized with a mysterious disease, he has to look to a training assignment they undertook in South Africa earlier in the year.