This achievement is found in Chapter 57 but, you need to find all of the other achievement orbs to unlock it. Here's a video with the locations of all achievement orbs including this last one.
Murky Waters - Chapter 6 (0:05)
Field Research - Chapter 7 (1:12)
Wee Wee Wee - Chapter 9 (2:15)
Left Behind - Chapter 15 (3:34)
Obscure Foundations - Chapter 16 (4:13)
Friends in Low Places - Chapter 30 (4:58)
A Tableau - Chapter 32 (7:01)
Pack Mentality - Chapter 32 (9:09)
Respite - Chapter 44 (11:46)
Unfathomable - Chapter 46 (13:04)
Clockwork - Chapter 48 (14:37)
Room for Reflection - Chapter 50 (16:10)
Office Space - Chapter 54 (17:38)
The Last One - Chapter 57 (19:36)