Stream The Secret Life of Dogs Online Free – Watch Full Movie from Home at 123Movies. . The Secret Life of Dogs explores how man's best friend experiences the world. Tap into dogs' inner psyche in order to determine the true meaning behind various behaviors and body language. Delve deep into canine biology as it is studied through slow-motion footage, thermal images and macro photography, providing new insights into how dogs drink, shake off water, and whether your best friend is left or right pawed.