Episode starts: Jerry lives in the wall between two apartments, one where Tom lives and the other where Lightning lives. He goes to the part inhabited by Tom and he spots an exposed chunk of cheese on the table. When he tries to approach, he gets hit with a fly swatter and runs away. It turns out that Tom has prepared an ambush for Jerry. When the mouse attempts to put his leg outside the hole, he gets it smacked flat. Having a wounded foot, Jerry withdraws to the Lightning's territory to avoid being chased by Tom's hand. Having reached the couch in the neighbor's half, Jerry runs away on his healthy food, as Lightning has spotted him.
After a brief calculation, Jerry gathers his courage and steals two of Tom's whiskers. He is attacked but tricks Tom into smacking Lightning with a fly swatter. He punches Tom back and both cats assume Jerry is a "super-mouse".
Tom prepares a second ambush with cheese, arming himself with a crossbow. Jerry takes the bait, so Tom shoots. The bolt avoids Jerry and cuts Lightning's tail instead, and gets stuck in a large swordfish. Tom believes he nailed Jerry, so he starts pulling the rope. With a little effort, the fish trophy leaves the stand and heads towards the mousehole. Lightning avoids being pierced, as the swordfish approaches. Tom ends up getting stuck in the swordfish carcass when he fishes it out of the other cat's apartment through Jerry's mousehole.
An armed conflict escalates when the cats decide to handle Jerry with ranged weapons and the mouse directs the cats' fire at each other. Lightning builds a brick wall and fires a slingshot at the mousehole. On the opposite side of the wall, Tom is preparing an old-fashioned cannon directed at the mousehole. He hears the movement behind the wall and Lightning's sling bullet pops out from the Molly Pitcher painting, hitting Tom at his mouth. Tom spits the bullet, relocates the gun at fires a cannonball at the picture. The round goes the same way as the bullet sling and destroys Lightning's brick wall.
Tom's attempt to blow Jerry with a dynamite stick fails, as Jerry rolls the stick under Tom's belly before the fuse burns. Tom hears it hissing under him and raises himself such that he is dazed, but not hurt, by the explosion.
Both cats then arm a hand grenade and throw it into the mouse's hole, but they hit each other and return to their owners. The two grenades go back and forth until the explosion of them occurs in each of their users' hands, damaging almost the entire wall. The cats give up and they then move outgoing abroad; Jerry whistles and follows them.
- This episode marks the return of Lightning Cat, except his skin color was changed into yellow instead of orange.