After co-authoring Volume 17, John Button, with Volume 18, "The Twisted Claw" (1939), took over the series full-time until 1942; McFarlane resumed with Volume 22, "The Flickering Torch Mystery" (1943). McFarlane's last contribution was Volume 24, "The Short-Wave Mystery" (1945); his wife, Amy, authored Volume 26, "The Phantom Freighter" (1947). Over the next several decades, other volumes were written by Adams, Svenson, Lawrence, Buranelli, William Dougherty, and James Buechler. Beginning in 1959, the series was extensively revised and re-written. Many authors worked on the revised books, writing new manuscripts; some of them also wrote plot outlines and edited the books. Among the authors who worked on the revised versions were Adams, Svenson, Buechler, Lilo Wuenn, Anne Shultes, Alistair Hunter, Tom Mulvey, Patricia Doll, and Priscilla Baker-Carr.