Take the brain in the jar (who will become your sidekick Brian). Pick up the Bunsen burner from the lab bench, then press the button on the wall and you will head through the open doorway. Use the Bunsen burner in your inventory to defeat the monster. Go through the door, then head up the stairs.
Examine the teddy bear twice. Pick up the telephone, then go through the door on the right. Pick up the mousetrap on the floor. Examine the pumpkin above the doorway twice and you will get a ball. Head back out to the hallway, then go through the archway on the left. Pick up the glass of water from the shelves (below the television). Leave through the door on the right to return to the hallway, then go up the stairs.
Go through the near door on the right to find a closet. Take the toilet paper, then leave again. Now head through the far door on the right. Use the mousetrap in your inventory to defeat the monster. Examine the tiger rug twice and you will head through a trapdoor.
Open the fuse box on the wall, then take the mouse from inside it. Now search the box nearest to the furnace until you take a king's crown. Keep searching until you find the fuzzy dice, then click on them to take them as well. Head out through the doorway into a games room. Open the small doors on the wall to reveal a dartboard monster. Use the fuzzy dice in your inventory to defeat the monster. Now take the blue remote control and keep clicking on it until you shrink yourself. Head right through the mouse hole.
You will automatically return to a normal size. From the kitchen, go right twice and then up the stairs.
Go through the left door to find another bedroom. Take the camera from the tripod, then head through the middle door. Use the toilet paper in your inventory to defeat the monster. Take the coat hanger and the kitty litter. Leave the bathroom, then continue through the left door to find another closet. Take the keys hanging on the wall, then move the clothes and go through the secret opening.
Search the books in the rack in the foreground until you take a book. Now click on the toy mouse in the right shelves to take it. Return through the trapdoor.
Exit the closet, then go through the right door and down the stairs.
Go through the left door into the dining room, then use the camera in your inventory to defeat the monster. Take the hairball from the dining table, then continue left to the kitchen. Click on the fridge twice, then use the book in your inventory to defeat the monster. Pick up the can of fish from the broken fridge. Return right twice and go down the stairs.
Head left into the laundry. Click on the laundry twice, then use the coat hanger in your inventory to defeat the monster. Take the towel from the laundry basket, then return right and up the stairs.
Go through the archway, then through the door on the left to find an indoor swimming pool. Use the towel in your inventory to defeat the monster. Click on the ceiling until a cat bowl falls down into the swimming pool. Now use the diving board and you will eventually get the cat bowl. Use the diving board again, and while you are jumping up and down, grab the chain to the left. You will end up flushed down through the drain in the bottom of the pool.
Click on the tiny plant in the large gray pot, then on the plant monster that appears. Use the glass of water in your inventory to defeat the monster. Pick up the catnip, then use the tree to leave the room.
Go right out of the dining room, then through the middle door. Use the keys in your inventory to defeat the monster, then go through the archway.
You should now have everything you need. Click on the big cat, then use the following 8 items in your inventory (in any order):
- dead mouse
- toy mouse
- cat bowl
- can of fish
- kitty litter
- hair ball
Now you can finally go through the main doors.