[Note: I played the Atari800 version on a Linux Machine. I’ve tried several roms and came across an Atari one (Circus.xex) that starts without the car keys and the pen knife in your inventory (I couldn’t find the items at all). It is not possible to win this version. The link below goes to a ‘clean’ dump of the game.]
You’re standing in a field in front of a circus tent with a petrol tank in your inventory. It suggests you stranded somewhere with your car.
GO EAST into a small enclosure where there’s a generator but no way to start it. It needs a cable. Let’s try to fix this one first. GO WEST back to the circus tent and GO SOUTH into the field where you’ll find a road. GO ROAD onto the roadside and GO SOUTH to the lay-by of the road. Your car is still here!
GO SOUTH to the rear of the car and OPEN BOOT to see the contents. TAKE SPANNER and TAKE FLASHLIGHT. From here GO NORTH to the front of your car and DROP KEYS. Now GO NORTH to the road side. You need to GO FIELD in order to GO NORTH back to the tent. GO TENT to find that it’s very dark in there.
LIGHT FLASHLIGHT to find yourself at the tent entrance. GO WEST to the store room and find a chest. You can’t open it but when you KICK CHEST it will fly open. LOOK CHEST to find thin slippers so TAKE SLIPPERS.
GO EAST again back to the entrance and GO NORTH into the ring. DROP KNIFE since you don’t need it …. yet. GO EAST again further into the ring. There’s a ladder going up so CLIMB LADDER onto a tightrope stand. Make sure to WEAR SLIPPERS and GO TIGHTROPE. If you careful GO NORTH then you’ll reach the stand on the other side. There’s a bar here so TAKE BAR.
GO TIGHTROPE again to return to the wire and GO SOUTH to reach the other side. To save inventory REMOVE SLIPPERS and DROP SLIPPERS. To climb down GO DOWN and GO WEST and GO SOUTH to the tent entrance.
LEAVE TENT to go outside and since it’s light here and to save batteries, UNLIGHT FLASHLIGHT. Now GO WEST and OPEN DOOR. You can since you’ve got a bar to pry it open. GO DOOR into the maintenance wagon to find a locker. What you did with the first lock, you can do again with the locker so OPEN LOCKER will force it open with the metal bar.
EXAMINE LOCKER to see what’s inside the broken locker and find a hacksaw. TAKE HACKSAW and GO EAST and GO EAST again to the entrance of the tent. GO TENT and LIGHT FLASHLIGHT. GO NORTH into the ring. GO EAST again further into the ring. There’s a ladder going up so CLIMB LADDER onto a tightrope stand.
CUT TIGHTROPE and it’ll fall to the ground. DROP HACKSAW since you don’t need it anymore. GO DOWN the ladder and TAKE CABLE. From here GO WEST and from here GO WEST once more into the mess room. There’s a freezer here. LOOK FREEZER and TAKE FISH out.
GO EAST back into the circus ring and GO SOUTH to the entrance. GO EAST again into a small room with a large tank. GO EAST again and you’re inside the large tank so you’d better SWIM. Only now you notice the seal. FEED SEAL and the animal will drop a snorkel. TAKE SNORKEL and GO WEST back into the small room and GO WEST once more to the entrance of the tent
LEAVE TENT to go outside. It’s light here and you don’t need it anymore so UNLIGHT FLASHLIGHT (just in case) and DROP FLASHLIGHT.
GO EAST to the generator and now that you have the missing cable you can FIX GENERATOR. You can try to START GENERATOR but it won’t. GO EAST into a large field. On the ground there’s a shovel. TAKE SHOVEL and DIG. This will result in a starting handle. TAKE HANDLE and DROP SHOVEL. From here GO WEST back to the generator. With the handle you can START GENERATOR again.
Now that the electricity is restored, DROP HANDLE and use the snorkel to SYPHON PETROL and fill your tank. DROP SNORKEL since you don’t need it anymore. Now GO WEST to the tent and GO TENT. This time you’ll be trapped inside. You’ll have to find another way out.
GO NORTH to the ladder and TAKE KNIFE. Now CLIMB LADDER to get to the top of the trapeze stand and then GO TRAPEZE. You’re now hanging on a trapeze. SWING TRAPEZE and while you’re on the highest platform, CUT CANVAS. Now there’s a hole in the tent.
You don’t need the knife anymore so DROP KNIFE. From here GO TRAPEZE to hang on the bar again and SWING TRAPEZE to return to the lower platform. GO DOWN to descend back into the circus ring. GO SOUTH to the entrance.
GO WEST to the store room and GO WEST again to find a closet. There’s also a clowns costume. TAKE COSTUME and GO CLOSET to see what’s inside. There’s a whip so TAKE WHIP. You can only exit with GO SOUTH.
In the store room GO EAST and GO EAST once more to the entrance of the tent. From here GO NORTH into the circus ring. There’s some rope so LOOK ROPE to see it’s not rope but a safety net. TAKE NET.
From here you can GO EAST further into the ring and GO EAST again to find a cage. WEAR COSTUME to get the attention from another clown and he can help you with ERECT NET to put it against the cage. You can safely REMOVE COSTUME and DROP COSTUME.
Now the exciting bit. GO CAGE to visit the sleeping tiger. CRACK WHIP and the tiger will leave. It appear he was sleeping on a trapdoor. DROP WHIP and GO TRAPDOOR into a gloomy passage. GO SOUTH into an equipment room where there’s a control panel. LOOK PANEL to find the button. PUSH BUTTON to open a hatch. GO HATCH to crawl behind the panel and find two terminals.
GO WEST into an alcove and see a blueprint. TAKE BLUEPRINT and then READ BLUEPRINT to find out what you can do to stop the detonation. DROP BLUEPRINT since you don’t need it anymore. GO EAST back to the terminals and SHORTEN TERMINALS to start the detonation. You have 24 turns to get out.
GO NORTH into the equipment room and GO NORTH again to the passage. GO UP into the tiger’s cage and GO WEST into the ring. GO WEST again further into the ring and GO WEST once more. You’re below a ladder again.
GO NORTH into the ring and GO WEST to find a huge cannon. LOOK CANNON to see a helmet. TAKE HELMET and WEAR HELMET. Now for the exciting finale! GO CANNON to see the lever. PULL LEVER just in time to get out. You’re back at the road.
GO ROAD and GO SOUTH to reach your car. GO SOUTH once more and FILL TANK. Now GO NORTH to TAKE KEYS to be able to GO CAR and DRIVE CAR to safety. You made it!
Game source: A copy of the game was found here on the internet.