'Castle' has been a stand out hit for ABC, it's season premiere was watched by over 13 million viewers.
Since its premiere in September 'Castle' has been able to keep a steady 11-12 million viewers.
Here is the break down of the last five aired episodes:
Episode 19 - 47 Seconds - March 26 - 11.87 million viewers
Episode 20 - The Limey - April 2 - 11.69 million viewers
Episode 21 - Headhunters - April 16 - 11.23 million viewers
Episode 22 - Undead Again - April 30 - 11.08 million viewers
Episode 23 - Always (Season Finale) - May 7 - 12.36 million viewers