As the final complete album in the Adventures, Tintin and the Picaros inevitably has a lot riding on it, more so when one considers that this was the only completed story produced by Hergé in the last fifteen years of this life. There are some signs that the series is aware that things are winding down and thus it tries to tidy up some matters. But at the same time this story also sees some changes to the regular characters, as though the intention was to take them into the last quarter of the twentieth century in a far more modernised pattern.
It's actually slightly surprising to see this album is kept in print. In many other comic traditions movies come and go, with a flurry of adaptations made at the time of the initial release but they usually then drop off the radar, going out of print and never being included in subsequent collections without much comment. But some of the Franco-Belgian comics instead keep the adaptations around, regardless of their status in canon. (Another example is the book The Twelve Tasks of Asterix, which is the illustrated text adaptation of the film of the same name, though the comic adaptation, with the English-language title "Asterix Conquers Rome", is long out of print.) Another curiosity is the title of this album - "Tintin and the Lake of Sharks" is almost a literal translation of the French "Le Lac aux Requins" but the English-language Region 2 DVD calls this "(The) Mystery of Shark Lake", with the "The" appearing or not in different places. (Even more strangely the French title is used on the sleeve cover.) It's not clear how this difference arose but one effect is to isolate the album from the source material to the point that it can appear to almost be a twenty-fifth adventure. The back-cover gallery on all of The Adventures of Tintin relegates this to the list of "Other Tintin Adventures to collect" (yes, plural, even when this sometimes the only one listed) but it can be found along with the other albums in bookshop displays to be obtained with all the rest, in spite of its status in the canon.