diff --git a/src/search.cpp b/src/search.cpp
index 4481cfc7..409ad20a 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -373,7 +373,7 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
   {
       Move bookMove;
       if (get_option_value_string("Book File") != OpeningBook.file_name())
-          OpeningBook.open("book.bin");
+          OpeningBook.open(get_option_value_string("Book File"));
 
       bookMove = OpeningBook.get_move(pos);
       if (bookMove != MOVE_NONE)