We describe the design, implementation, and evaluation of a comparative book reader that supports the scholarly activities deemed most important by cultural history scholars. A filmstrip metaphor allows rapid access to various components of the books. Parallel filmstrips allow comparison among multiple copies of the same title to fill in for missing pages or other maladies, and to study page-level annotations to help in interpreting the content. Playing the filmstrips allow the scholar to search for or discover items of interest by watching the pages of the books flow past. The need for a canonical book and possibly multiple "Frankenbooks" is described and the implementation is given. The architecture of the tool and the programming methodology are also described. The results of a discount usability study are presented along with lessons learned and future directions for improving the comparative book reader.