Castle season 4 has 23 episode guides and currently identifies 66 soundtrack songs.
Castle season 4 episodes
Episode 1
Sep 19, 2011
3 songs
Episode 2
Sep 26, 2011
5 songs
Episode 3
Oct 03, 2011
1 song
Episode 4
Oct 10, 2011
2 songs
Episode 5
Oct 17, 2011
4 songs
Episode 6
Oct 24, 2011
2 songs
Episode 7
Oct 31, 2011
1 song
Episode 8
Nov 07, 2011
8 songs
Episode 9
Nov 21, 2011
2 songs
Episode 10
Dec 05, 2011
2 songs
Episode 11
Jan 09, 2012
8 songs
Episode 12
Jan 16, 2012
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Episode 13
Jan 23, 2012
5 songs
Episode 14
Feb 06, 2012
3 songs
Episode 15
Feb 13, 2012
1 song
Episode 16
Feb 20, 2012
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Episode 17
Feb 27, 2012
2 songs
Episode 18
Mar 19, 2012
4 songs
Episode 19
Mar 26, 2012
4 songs
Episode 20
Apr 02, 2012
2 songs
Episode 21
Apr 16, 2012
1 song
Episode 22
Apr 30, 2012
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Episode 23
May 07, 2012
6 songs