Henri Bencolin was Carr's first series detective. These are the second and third books (of five) in which he appeared. Spine tears, a clipped back cover corner and some lesser exterior wear (plus some writing on the first pages) in SKULL; loss of some of the yellow film and Perma-Gloss peeling along cover edges, plus some more modest cover/spine flaws (interior appears unmarked, though some pages are uneven) in GALLOWS. These titles are less often seen than many other Carr mysteries.