Note that I'm basing the shows on where they are situated, and don't have to necessarily be in their completion.
You will disagree, get over it.

20. Suits
19. Community
18. House M.D.
17. Luther
16. X-Files
15. Dr. Who
14. Sherlock
13. 24
12. Battlestar Galactica
11. Twin Peaks
10. Rome
09. Homeland
08. Lost
07. Dexter
06. Sopranos
05. Arrested Development
04. Buffy the Vampire Slayer
03. Game of Thrones
02. Six Feet Under
01. Breaking Bad