A spy series set, according to Moran in his Guide to Australian TV Series, 'very much in the same locale and situation' as Contrabandits. The two spies work for FIASCO (Federal Intelligence and Security Control Organisation), run out of Canberra by the never-seen and rarely heard Dave Shannon.
Moran notes that Shannon's Mob was glossier than Contrabandits, but also mundane:
In its own eyes the company had made a fundamental mistake in not coming up with a formula that used some real point of Australian difference. Many other countries had harbours, boats, and water. For that matter the special investigation team headed by Shannon was very ordinary indeed.
In his Classic Australian Television, however, Don Storey suggests that 'The spectuacular scenery, particularly of the Harbour, is fully exploited.'
Shannon's Mob received poor treatment from the network (which persistently delayed its televisation) and was widely panned by critics when it did air, perhaps in part because the popularity of spy stories had peaked some decade earlier. Storey concludes:
It would be easy to suspect that the treatment of Shannons Mob, coinciding as it did with the cancellation of the three Crawford cop shows (Homicide, Division 4 and Matlock Police), was part of the plot to sabotage Australian production. However, there is no evidence or even speculation to suggest that anything was deliberately done against the series - although it would be safe to assume that in the prevailing climate nothing positive would have been done to help the series either.
In an early report on the series, The Australian Women's Weekly noted, 'All writers for the series will be Australian, and among them will be some of those who produced the most successful of the "Boney" scripts' (Wed. 10 October 1973, p.10).