3 Days: Zoo Mystery is a hidden object adventure game developed by the company, Realore Studios. The player takes on the role of Anna, whose uncle operates a local zoo. Several animals have started to disappear mysteriously and Anna’s uncle enlisted her help to recover the animals and find out who and why they disappeared. She has to accomplish this task before Friday, when the zoo inspectors arrive. If Anna fails to find the animals in time, the inspectors will order the zoo to be shut down completely. Anna has three days to prevent this from happening.
The player must explore various areas at the zoo and find different items concealed strategically around them. Some of the objects are divided into fragments, requiring the player has to locate each piece and put them all together. The game presents the player with different habitats, and it is up to him/her to determine what kind of animals live there before searching for them. Certain items in each scene can be moved by the player such as lamps and drawers in order to find hidden objects. Once the player gets halfway through the game, s/he earns a simple device that helps carry heavy objects. Mini-games can be played at random moments in the game, and each of them involve a different task like fixing a broken alarm and retrieving a set of keys from a tank of piranhas.