Sylvester is in pursuit of Tweety, chasing him to the top of a building. Sylvester falls from the building (first he grabs some of Tweety's feather to help him fly, but Tweety takes them back), crashes on to the sidewalk (which cracks) and dies. The spirit of his first life approaches two escalators and takes the "down" (to Hell) one (since the one going "up" (to Heaven) is roped off) and ends up in Hell. A Satanic bulldog (Hector the Bulldog) welcomes a terrified Sylvester. He realizes that he must goad Sylvester into giving up his remaining eight lives, so he asks #1 to sit on a bench to wait for the others.
Sylvester wakes up and Tweety tells him he's in trouble for breaking the sidewalk (which cracked upon impact of his earlier fall). Sylvester has had enough and tells Tweety he doesn't even know what "trouble" is and orders him to get lost. The bulldog's spirit reminds him that he has eight lives left, so Sylvester starts the chase up again. He chases Tweety around a moving steamroller but gets flattened, sending life #2 through the street and into Hades. The flat #2 gets up and sits beside #1.
The chase then continues through an amusement park. They both run into a dog's mouth entranceway to the fun house, but Sylvester steps back out, takes one look at the dog and is literally frightened to death. As scared-white-as-a-sheet life #3 takes his place on the waiting bench, the cat recovers and finds Tweety amongst the moving targets in a shooting gallery. He climbs into the targets to get at his prey but is shot several times in rapid succession. With each shot, lives 4 through 7 pop up on the bench. Sylvester bursts out of the gallery (after narrowly missing another shot) and sees Tweety heading towards the roller coaster. As Tweety sits in the front seat, proclaiming "that puddy tat will never find me here", the cat takes the seat directly behind him. The train ascends the lift hill and proceeds to go through the drops and turns. Near the end of the ride on straight track, Sylvester stands up. Just as he's about to pummel an unsuspecting Tweety, Sylvester slams into the entranceway of a tunnel. Upon impact, the train carrying life #8 in the front seat runs through the tunnel and down Hades' twisted conveyor route that took Sylvester's first life down earlier.
Recovering, Sylvester realized that he only has one life left. The bulldog again goads him to go after Tweety, but Sylvester screams "No, no, no! I don't want him! I don't want him!" and runs off. He decides to move into a bank vault with several cans of food, commenting that he'll be safe in there and nothing will happen to him. Later that night, two bank robbers try to break into the safe, but fail when they use too much nitroglycerine and end up killing themselves and Sylvester. As the three of them go down the escalator conveyor to Hades, one of the robbers tells the other, "Yer used too much, Mugsy." The disgruntled #9 adds: "Now he tells him!"
In the scene where Sylvester loses four lives in the shooting gallery, he is actually shot five times. Somehow, the first shot does not cost him a life. After the second shot, the scene cuts over to the waiting bench. Life #4 is there as a result of that second shot, then #5, #6, and #7 appear alongside one another.
The version of this cartoon shown on CBS' The Bugs Bunny/Road Runner Show had two parts edited:
Sylvester trying to get Tweety on a moving rollercoaster and ends up losing his eighth life when he hits the top of the tunnel. The CBS-edited version shows Sylvester speeding towards the tunnel, followed by an abrupt cut to Sylvester's eighth life riding a rollercoaster car into Hell.
The ending where Sylvester holes himself in a bank vault with food and water so he won't be tempted into losing his final life, only to lose it when two bumbling safe-crackers use too much nitroglycerine to blow up the vault. The CBS-edited version ends the cartoon after the devil dog urges Sylvester to go after Tweety and Sylvester shouts, "No, no, no! I don't want him! I don't want him!"