After Bikini Bottom destruct the sea monster move to rock bottom. Army try stop them. They fail so they decide bring Spongebob Squidward Patrick Mr. Crabs and Sandy back to life using dna. However mad scientist who causing attack is bringing more type of sea monster to life.
"They not be able to stop creature!" mad scientist say. Secret agent watch this. "I stop him!" he think.
In lab Spongebob Squidward Patrick Mr. Crabs and Sandy wake up. "I thought we dead!" Sandy say. "We bring you to life!" army man say "So you able to stop sea monster!" "Ok!" Patrick say. "We need weapon!" Squidward say.
Army man hand them gunns. "Use these!" he say. Then army captain run in room! "Army base under attack!" he say. They run outside and see sea scorpions attack building. "OH SHIT!" Sandy say. "We must stop them!" Spongebob say. Everyone shoot at them.
Then sudden the sea scorpion retreating! "What the hell?" Sandy say. Then see bigger sea monster head toward them. "OH NO!" Sandy say. "It Megalodon!" army captain say. "EVACUATE!" army leader say.
Everyone but Spongebob and friends leaving army base. "Why you not follow?" army man ask. "We stop Megalodon!" Spongebob say. "Good luck." army man say "You need it." Army man run way like cowerd.
Megalodon head toward Spongebob and others. "You sure this good idea?" Squidward say. "Of course!" Spongebob say. They fire gunn at Megalodon. sea scorpion return. "We outnumbered!" Patrick say. "We not give up!" Spongebob "Or world doom!"
Spongebob throw gerbade at sea scorpion to distract. Patrick head for launcher of missile to attack Megalodon while scorpion distract. When Patrick grab launcher sea scorpion no longer distract. sea scorpion heading to Patrick. Spongebob shoot atomic ray at scorpion killing them. Atomic ray run out. "SHIT!" Spongebob say.
Megalodon swim toward Spongebob. Patrick shoot at Megalodon. Megalodon die. "We defend base!" Spongebob say in happy. Army cheer.
In mad scientist hq mad scientist is angry. "Time to release biggerer sea monster!" he say. Then secret agent attack! Epic battle start while biggerer sea monster in cage.
Then biggerer sea monster break out of cage! "Fuck!" secret agent say. "YES!" mad scientist say. Then mad scientist computer go crazy. It start create billion of sea monster. "NO!" mad scientist say. "YOU FOOL!" secret agent say "You not run viruses scan!"
Secret agent kill mad scientist. Secret agent try kill computer. Secret agent eating alive by sea monster.
At new army base Spongebob and other briefed new mission. "We find place where sea monster come from." army leader say as point to building on map "You destruct it!"
"Ok!" Sandy say. Army leader drive them to building on map. Army leader gasp. "Oh crap!" army leader say then say on walkietalky "Backup need!"
Ton of sea monster round building. "You kidding me!" say.
Backup come to building. "How we stop monster!" army man say. "We shoot them we out of nuke!" army leader say. Then Liopleurodon attack boat with Spongebob and others. "RRRRRUUUUUUNNNNN!" Sandy say. They run way as Liopleurodon to big to fight.
Computer creating more sea monster. "We shoot computer!" Spongebob say. Bulet bounce of computer as force field round it. "We need get closer!" Squidward say.
Liopleurodon eat much army man long with other sea monster. Squidward try shoot Liopleurodon then Basilosaurus attack. "FUCK!" Squidward say. Mr. Crabs try protect Squidward. Mr. Crabs eating by Basilosaurus instead.
"NO!"Spongebob yell. Patrick tank attack Basilosaurus. Basilosaurus flip tank over. "I trapped!" Patrick say. "I save you!" Spongebob say as shoot Basilosaurus to distract.
Basilosaurus swim toward Spongebob who run way. Squidward flip over tank so Patrick shoot Basilosaurus kill it. 100 Nothosaurus attack tank overwhelm Patrick. Patrick get out run way. Nothosaurus swim after Patrick. Squidward fire missile at Nothosaurus then Pterosaur attack.
"What we do?" Sandy say. "We fight!" say Spongebob. Spongebob shoot Pterosaur as Squidward shoot Nothosaurus. Sandy see 50 Ambulocetus swim toward her and army man. "DIE!" she yell as she and army man throw gerbades at them.
Meanwhile army leader and army man try fight Liopleurodon. Then Mosasaur attack army leader. Army man save leader but eating alive.
"We loosing battle!" army leader say. "Not give up!" Spongebob say "We world only hope!" "Some one must stop computer as it create more prehistoric creature!" Sandy say. "I will!" Spongebob say. "It too dangerous!" Patrick say. "I must!" Spongebob say "Or world die!"