The Empty City is succeded by A Hidden Enemy
:The story starts out with Lucky and his friend; a female dog named Sweet. They are stuck in the Trap House when the big growl (earthquake) arrives. Sweet manages to escape and helps Lucky get out of his cage. They get out of the Trap House and as far away from it as possible. They find some food in trash cans and encounter racoons on their way to where Lucky leads Sweet. He stops at the Food House and teaches Sweet how to beg before waiting patiently at the door of the Food House. After waiting awhile at the door Lucky steps into the wrecked building and becomes confused at what he sees. He looks for the nice longpaw (human) who gave him food and finds him crushed beneath the building. The longpaw is weak, paled faced, and barely breathing as Lucky trys to wake the longpaw up. The longpaw lives long enough to see Lucky then dies. Sweet scampers off and Lucky goes after her and pins her down. Sweet says she just can't stay here anymore. Lucky and Sweet part ways and Lucky is alone again.
Along the way Lucky smells food and finds a steak. Thinking that the longpaw and the fierce dog that were near dead he tried to take it, but awaked the longpaw and it's fierce dog. The fierce dog chases Lucky into a hole were the ground has split from the big growl and he stays there for the night. Once it is morning he somehow gets out of the hole and starts to head towards the mall. He encounters an old friend named Old Hunter. Lucky sees all the foods he has and at first Old Hunter is reluctant to share, but after Lucky saves his life he decides to share. Once Lucky finishes eating Old Hunter hives him a piece of meat for him as a gift and Lucky goes his seperate way. Some foxes find him and start chasing him for the piece of meat from Old Hunter. Lucky tries to escape but the foxes corner him. Right when Lucky thought he was doomed a bunch of dogs come in and save him. One of the dogs named Bella reconize Lucky as Yap his puppy name. Lucky then remembers the dog as Squeak his sister and one of his littermates. Bella introduces herself to Lucky and the other dogs; Martha, a Newfoundland; Mickey, a border collie; Bruno, a German Shepherd; Sunshine, a Maltese; and Daisy, a Westie and Jack Russell Terrier mix. He figures out that these dogs are leashed dogs, or pets, who lived near each other and are hoping their longpaws will come back to get them.
Lucky decides to help his little sister and temporarily join this "leashed pack". The dogs go back to their homes and sleep there. During the night the houses in which the dogs were sleeping in collapsed. They all make it out of the houses, but then Sunshine remembers that a dog named Alfie was still in his longpaw's house and claimed that he stayed at his house to guard it. Lucky and Bruno are the only brave dogs to go and get Aflie.They successfully get Alfie and decide to get out of the city, but before they leave Lucky agrees to let them take one item to remember their longpaw's by. Once they leave they encounter shiny yellow-suited and faceless longpaws and what looks like a lake but isn't. They keep moving on until they find a good place to make their camp with clean fresh water. They play in the water and be careful to stay away from the rapidly flowing water in the river, but even so Bruno gets to close and drowns but Martha saves him. Lucky decides it was time to teach them how to hunt, but after a few tries he starts them out with something easier, bugs. Later on the dogs have learned how to catch prey for real with Mickey as an excellent hunter, but then Sunshine reports that when Mickey was teaching her how to hunt he got caught in some thorns.
Lucky frees him and tries to persuade the dogs to take off their collars, but they refuse. The dogs return to came to Alfie's relief; thinking that he was lost. A couple of days later Alfie reports that he had sighted a place with tons of food, and they should invesigate. Lucky seems uncertain about this and got into an arguement with Bella and she made the decision that Lucky, Daisy, Alfie, and herself would go check it out while the rest watch the camp. Alfie leads the way and soon enough they find the place. Lucky and Bella have another arguement and it ends out with Lucky staying behind while the rest went on. Lucky watched as Daisy dug a hole so they could squeeze under the fence. Lucky stayed there for awhile then decided to go in. He saw Bella, Daisy, and Alfie eat away all the food that kept rolling down from some sort of tube. Lucky seemed it was safe, but right then some big sleek dogs came and took the three dogs away. Lucky figured out the dogs names were; Blade, Dagger, and Mace. He knew he had to help them so he lured the dogs towards him with insults while the others ran free. Once he was sure they were gone he made a run for it and barely escaped with his life. He found the others and they apoligized and went back to camp.
The three dogs told the rest of the dogs at the camp about what happened then Lucky announced that they should leave. The dogs solemly agreed and took off. Upon looking at what was left of their city Bella stopped and commanded the dogs to bury their items from their longpaw's houses so they could forget about their past. They complained but after awhile gave in and buried the items; except Mickey who asked Bella if he could keep his so they could at least have one memory and Bella agreed to let him keep his item. Lucky lead them to a place where he was sure they would be safe. Once they settled a bit Lucky decided that this would be the best time to leave. He announced his leaving and they pleaded him to stay, but he said to them that he was a lone dog at heart. Bella said that they would give hime time to think and tomorrow whatever choice he made they would accept and not try to stop him.
The next day his mind was still set on leaving, but Lucky wished that it didn't hurt so bad. He said goodbye to all of them then left. After going some way away from their camp he heard the noise of fighting. He raced back to their camp with only one thing on his mind as his muzzle drew back, baring his fangs for a fight... they were his pack. Lucky's Pack... and they were in trouble. I'm sorry if the plot was too long and please forgive me if i misspelled something. Oh, and I'm nost sure if I am correct but I think the faceless yellow-suited longpaws Lucky said he saw was a longpaw with a shiny, plastic like, yellow-suit; that coverd their heads too. And with a black screen that is apart of the suit that covered the front of their face so they could see and breathe. Probablly they had those things on because of the earthquake ... but I'm just guessing.