A sharp variation of the Ruy Lopez 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Bc5 for Black repertoire. The book is divided into 4 chapters: in the first author discusses the critical position that arises after 6.c3 0-0 7.d4 Ba7, where he analyzes all the possibilities of White. The second part examines the sidelines in the White's 5th and 6th moves. The third chapter deals with the Exchange Variation 4.Bxc6. The last chapter contains exercises and solutions. Several indexes. The variation, which is named after the Danish master Jorgen Moeller (1877-1944), is currently popularised mainly by Magnus Carlsen. 2 pictures. Further information about the book is available at newinchess.com