The Swedish editions, released in the period between 1971 and 1975, were published by arrangement with Western Publishing. All six titles form part of the POP series of popular titles for younger readers. Other authors that also had titles published as part of this series include Enid Blyton, Julie Campbell and Ruby Ferguson, in addition to several other home-grown Swedish authors.
The books are unique for two particular reasons. The first is that all six titles are credited to Charles Spain Verral, whose name is featured prominently on the book covers. Secondly, and perhaps most notably, the nickname that gives the series its name – Brains Benton – was changed by translator Lasse Mattsson to the Swedish equivalent of 'Professor' Benton. Consequently, this is the only set of foreign editions where Barclay Benton is referred to as 'Professorn' in the narrative, as opposed to the more familiar 'Brains' handle.
While the books do not contain any internal illustrations, the charming and charismatic cover artwork is by noted Swedish artist Ola Ericson, who also happened to illustrate the Swedish Three Investigators editions.
According to the copyright pages of the books, Missing Message and Counterfeit Coin were not issued with ISBNs at the time of publication. In addition, Stolen Dummy appears to be the only title to have been released both in trade and library editions.