When Toshiaki digs it up to use Victor Frankenstein's reanimation secrets on it, the experiment goes awry and the resurrected turtle grows to an enormous Godzilla-sized turtle after getting doused with Miracle Gro whilst being struck by the lightning.
Turtle Monster then begins to rampage around the town and then the dutch day festival stomping and crashing cars, destroying everything in sight. Toshiaki needs Victor's help to resolve his problems, so Victor and Toshiaki and Bob went to the dutch day festival to stop The Turtle Monster, Toshiaki went to the ferris wheel to take a video on his monster pet but the beast approached Toshiaki and began to attack him, however victor managed to stop the beast after throwing a live cable into the puddle Shelley was standing in, thus elecrocuting the monster and reverting it back into the dead turtle it once was.
- Turtlezilla is like Godzilla
- Unlike the other monsters, which were meant to reflect the classic Universal Studios movie monsters, Shelley was meant to resemble Gamera , a Japanese kaiju monster by Kadokawa Pictures . References also allude to those of classic pop culture monster Godzilla, rival monster of Gamera.
- In this movie, the Turtle Monster is voiced by Dee Bradley Baker.
- It's possible Shelly's name is a reference to Mary Shelley, the author of "Frankenstein", on which both the short film and 2012 film are based.
- The reason why Shelly grew to this size because of the miracle grow in toshaki's backyard while being re-animated by Toshiaki
- The Monster Turtle resembles a Tyrannosaurus Rex, king of the dinosaurs
- He ate some Sea Creatures that were on the phone booth where Mr. and Mrs. Frankenstien were in. He may have accidently saved them.
- The third film in the Frankenweenie frankensize is named after him.