This is a comprehensive list of the differences between the TV series and the story.

TV series Zak Saturday's Immortal Love Life
Neither Sarah nor any members of her family were apart of it or even mentioned. Sarah and her family are apart of the Saturday's lives and adventures.
Once the Saturdays return to their airship after being chased by a group of flashlight frogs, the alarms for their house immediately go off. The alarms don't go off until Sarah wakes up and explains her story.
Drew saved Doc from Van Rook's apprentice with her fire sword before Zak, Fiskerton, and Komodo entered the room to help them. Sarah, using her sword, saved the Saturdays from Van Rook and his apprentice after they had injured the Saturdays.
When the Saturdays fell off the cliff, Doc and Drew used their grappling hooks to save them, Drew (unintentionally) giving Zak a power-wedgie in the process. Sarah used her Pokémon, Charizard and Latias, to catch them all and fly them safely back to the top of the cliff without giving Zak a power-wedgie.
Zak fought Argost and Munya alone after they had taken the last piece of the Kur Stone from them. After she got herself free from the vines, Sarah helped Zak fight them.
When Zak bought the Talking Argost action-figure, he paid thirty-two dollars for it because of the unreasonable salesman. Sarah threatened the salesman with her sword to allow Zak to pay his first price, which was twenty dollars, and called him an ass in the process.
When Zak almost got run over by the train, he used his claw to escape being hit. Sarah lunged for him, grabbed him, and pushed him out of the way, her landing on top of him in the process.
Zak threw a snowball into Fiskerton's face with his claw before he lost it. Zak accidentally threw the snowball into Sarah's face instead of Fiskerton's.
Zak got the satchel with all the artifacts that Van Rook stole himself. Sarah and Zack got the satchel and then threw it to Zak.
Zak took Fiskerton's green sash, and Komodo took his, making him the winner. Sarah took Fiskerton and Zak's green sash and Zack took Komodo's, making them the winners instead.
They rode Fiskerton's bicycle toward the front gate after drowning Piecemeal and ran into the force field. They just ran toward the front gate, and Zack summoned a fire ball, throwing it at the force field, and it launching back at them, knocking them to the ground.
Fiskerton pounded the control panel to open the small doors with the cortex disruptors in them. Sarah used her powers to get into it.
Drew used her fire sword to cut the power lines to fall onto the water and electrocute the lava lizard. Drew had Raylee tell Pikachu to use Thunderbolt on the water.
Zak used his claw to knock Munya down the cliff. Sarah and Zack kicked him down it.
Zak kicked Zak Monday away to use his claw and cut away the ropes around his hands. Someone used a fireball to blast Zak Monday away and Zak got his claw.
Wadi drove the DRV to the place where the Methuselah Tree was. Sarah drove instead.
Zak got the sap and then dropped it. Sarah had gotten it and then dropped it.
Zak, Drew, and Doc went out and took photos of all the people in the temple. Raylee used her powers to get all of the photos for the Saturdays.
Zak, Fiskerton, and Komodo rode on Fiskerton's trike through the swamp. They never got his trike. They just walked through the swamp.
Fiskerton saved Zak from the alligators by grabbing onto the branches of the trees around them. Sarah used her powers to fly and save Zak from them.
The Saturdays fought the cryptids away when they attacked them in the lab. Raylee had Pikachu use her electricity to scare them away.
Fiskerton grabbed Zak when he fell off the bed post and almost onto Komodo. Sarah grabbed him instead.
When the people of the city attacked the Saturdays, the electricity hit them all except Drew. Raylee summoned a force field to protect them all from it.
Fiskerton throws Piecemeal out the side of the train. Sarah and Zack kick him outside of it.
When Piecemeal comes back, Argost had his neural parasite shock him before he could take a bite out of Fiskerton. Sarah kicked him out of the train again.
The guillotine fell between Doc and Doyle while they were standing. Amber and Shillow knocked them away and onto the ground to avoid it.
When Zak accidentally stepped on the blue tiger's tail, then grabbed onto it when it started running from him, Wadi stopped the tiger from dragging Zak around the area. Sarah got the tiger's attention and stopped it.
Fiskerton and Komodo weren't captured by Shoji Fuzen's men, and they helped the Saturdays get out of his dungeon. Fiskerton and Komodo were also captured, and Nikki and her sister helped get the Saturdays and the Hollingers out.
When Wadi got the blue tiger again, she kicked the traps that were around it toward the guards and they blew up. Sarah threw her fire balls at them and scared them away.
The Saturdays had used their belts to go across the elevator and over the chasm to get to the other side. Sarah and Zack summoned ropes for them to use instead of their belts.
When the serpent woman tried to get through the swirling vortex around Fiskerton, Zak hit her in the head with the claw. Sarah high-jump-kicked her away.
When the Mondays appeared, Zak Monday had used his powers to control Fiskerton right after Zak called them "The Mondays." Danielle and Daniel were with the Mondays, therefore, Zak Monday didn't get the chance to control Fiskerton until they took Zak, Fiskerton, Komodo, Zon, and Zack to where the smoke mirror was.
Doc, Drew, and Doyle didn't know that the boys and Zon were in Paris until they got to their airship. Selena had called Sarah, informing her that the boys were in Paris before they got on the airship.
Doc, Drew, and Doyle fought their way through the Secret Scientists to get to their airship. They fought them a little bit, but the animals mainly handled the fighting for them so that they could get to the airship.
Dr. David Bara used a statue to make Fiskerton fall asleep. Sarah used her powers to do it for him.
Doc lunged at Beeman on his UFO ship on the river. Sarah attacked him instead.
Argost knocked Rani Nagi off the sea creature by throwing a board of wood at her. Sarah used her fire ball to knock her off instead.
Miranda used her gadget to teleport Deadbolt to another spot on the water, and he crashed into a boulder, breaking into pieces. Sarah just used her fire ball to burn through his chest, and it destroyed him.
Drew used the line that was connected with her speedboat with Komodo's raft to knock Miranda off of her speedboat and she skipped off the shore and into the forest nearby. Sarah used her fire ball to knock her off and launched her into the forest.
Drew and Doc kicked Gokul to end the ceremony from killing Zak. Sarah summoned a lot of her power to break through the force field around Zak, ending the ceremony.
When Epsilon and Francis grabbed Zak the first time, they dropped him when Epsilon was holding him with one of his robotic arms and threw him to Francis, who wasn't able to catch him because Drew cut off one of his robotic arms with her fire sword. The amethyst on Sarah's necklace glowed and emitted a strong power, forcing their robots to temporarily malfunction and drop Zak.
Zak, Fiskerton, and Komodo rode Fiskerton's Fiskertrike through Turkey to distract Epsilon and Francis from stopping Doc and Drew. Sarah transformed herself into a werewolf, and they rode her through Turkey.
When the flying creature was carrying the calopus toward Drew and Wadi, once it landed, Doc jumped on top of it, stopping it. Sarah throw a fire ball at them while they were still in the air and knocked them away.
Zak used one of the satellites around him to get the morphing cryptid in bull-form's attention. Sarah used her powers to get the cryptid's attention.
Argost pushed the lever on the pool to block the morphing cryptid from getting out. Sarah pulled it instead.
When Rani Nagi knocked Drew away from Argost and into the wall, when she was going to strike Drew again with her fire sword, Van Rook intercepted it with his own body. Sarah used her fire powers to knock Rani Nagi away from Drew, warning her to stay away.