The Zoo level begins when you pass a metal gate with “Zoo” written on it. Convenient, right? Continue to the left and your first character will get snatched away from a monster that resembles the guard from the beginning of the game. A hunter will appear and chase after the beast.
Hop the gap, go down the ledge, and head right. Continue right and jump the gap here. You will find the hunter who is podcasting (no really, she says, “hunter podcast”), when her recorder breaks, she will throw it at you.
Pick up the recorder and return left, then down the gap. Now continue right until you come to another gap with a ladder. Descend the ladder and head left. You will cross a rickety bridge and a ladder, but do not use it. Keep heading left and you will find the Crystal Cave Monster. Run at the monster and he will bite you, then toss you over his shoulder where you will find your thought-to-be-dead friend.
Climb the ladder here all the way to the top, then jump to the platform on the left. Here you will find a cage. Push this cage down to the ground level, then push it up against the left hand wall. Now hop up on the cage and you will be able to reach the high ledge. Go over the ledge and continue left until you come to gap.
Drop down in this gap and you will find a dead clown, a dead robot, and bones. Use the action button on the dead robot and a fuse will pop out. Take the fuse and return back to where the monster was. Drop the fuse and use the tape recorder on it to combine the two. Now have one of the characters without the tape recorder pull the lever at the ledge above the cage to open a trap door.
Send the other two characters through the trap door. Here you will find another lever to pull. Have the empty handed character pull the lever and send your other character through the open door, then back up to the floor with the zoo gates. Instead of going right, go left this time and you will find an eel tank. Hop in the eel tank and a shock will jolt the battery, getting the tape recorder to work again.
Now return back to the monster and set the camera down next to it, then run at the monster and get eaten again. Return to collect the tape recorder, pick it back up, and return back up to the hunter. Set the tape recorder on the ground by the hunter and the noise will send the hunter after the monster.
Now that the hunter is gone you can use the hot dog machine. Pick up the hot dog and take it back down the monster. After crossing the bridge you will find the monster is now patrolling the hall. Get close enough for the monster to smell the hot dog and lead it onto the crumbling bridge. The weight of the monster will cause the bridge to collapse and the hunter will continue after it.
Hop down the newly created gap to find the mission.
Article from Gamersyndrome.com