CREATE TABLE table_20726262_4 (no_in_season INT, usviewers__million_ VARCHAR)

what is the maximum number in the season wher the us viewers is 2.59?
SELECT MAX(no_in_season) FROM table_20726262_4 WHERE usviewers__million_ = "2.59"
SELECT MAX("no_in_season") FROM "table_20726262_4" WHERE "2.59" = "usviewers__million_"