CREATE TABLE table_18081 ("Complete Series" CLOB, "Region 1" CLOB, "Region 2" CLOB, "Region 4" CLOB, "DVD Extras and Bonus Features" CLOB, "Number Of Discs" FLOAT)

Name the region 4 for the complete fifth series
SELECT "Region 4" FROM table_18081 WHERE "Complete Series" = 'The Complete Fifth Series'
SELECT "Region 4" FROM "table_18081" WHERE "Complete Series" = 'The Complete Fifth Series'