The investigation was conducted Season 4
Season 4
Air date: 2009-02-06
Episodes: 26
Episodes
E1: Episode 1
Air date: 2009-02-06
• ★ 7
E2: Episode 2
Air date: 2009-02-13
• ★ 7
E3: Episode 3
Air date: 2009-02-20
• ★ 7
E4: Episode 4
Air date: 2009-03-06
• ★ 7
E5: Episode 5
Air date: 2009-03-20
• ★ 7
E6: Episode 6
Air date: 2009-03-27
• ★ 7
E7: Episode 7
Air date: 2009-04-03
• ★ 7
E8: Episode 8
Air date: 2009-04-10
• ★ 7
E9: Episode 9
Air date: 2009-04-17
• ★ 7
E10: Episode 10
Air date: 2009-04-24
• ★ 7
E11: Episode 11
Air date: 2009-05-22
• ★ 7
E12: Episode 12
Air date: 2009-05-29
• ★ 7
E13: Episode 13
Air date: 2009-06-05
• ★ 7
E14: Episode 14
Air date: 2009-06-11
• ★ 7
E15: Episode 15
Air date: 2009-06-19
• ★ 7
E16: Episode 16
Air date: 2009-06-26
• ★ 7
E17: Episode 17
Air date: 2009-09-11
• ★ 7
E18: Episode 18
Air date: 2009-09-18
• ★ 7
E19: Episode 19
Air date: 2009-09-25
• ★ 7
E20: Episode 20
Air date: 2009-10-09
• ★ 7
E21: Episode 21
Air date: 2009-10-16
• ★ 7
E22: Episode 22
Air date: 2009-10-23
• ★ 7
E23: Episode 23
Air date: 2009-11-13
• ★ 7
E24: Episode 24
Air date: 2009-11-20
• ★ 7
E25: Episode 25
Air date: 2009-12-18
• ★ 7
E26: Episode 26
Air date: 2009-12-25
• ★ 7