Lincoln is a former major antagonist in the Dog Man series. He appears as one of the two main antagonists in Dog Man: Unleashed (alongside Flat Petey) and as the main antagonist in Dog Man: A Tale of Two Kitties, before redeeming himself in the end and appearing as a secondary protagonist in Dog Man: Fetch-22.
In Dog Man Unleashed, Dog Man bought Flippy for free from Penelope's Pets and gave him to Chief for his birthday, while the other police officers gave him a can of Supa Brain Dots. Chief then puts his can of Supa Brain Dots and Flippy into another room, where he eats one of his brain dots. After Chief leaves for lunch with the others and slams the door closed, the can of Supa Brain Dots topples over and the brain dots fall into Flippy's tank and his brain grows 11 times bigger, giving him psychokinetic powers.
After discovering how his powers work, Flippy cuts out a hole in a paper bag, steals a purple trench coat and an orange, three-legged stool with black stripes from Chief to dress himself up as a human, becoming the Mysterious Stranger. He robs Penelope's Pets, ties up Sarah Hatoff, Zuzu, two Penelope's Pets workers, and then he steals a bunch of little plastic treasure chests, planning to get enough gold to buy the biggest castle in the city. Fortunately, Zuzu chews through the ropes and Sarah snaps a picture of the Mysterious Stranger. She thinks he's Petey the Cat, because the orange-and-black-striped-stool looks like his tail and legs, and posts it on her news blog. The news reaches Petey at Cat Jail, and he gets enraged because he thinks someone is impostoring him, and he escapes Cat Jail, using a paper Petey (which is brought to life by the Witch Doctor Boog. E. Feeva later in the story) as a distraction and built the Treasure Tank 2000 in his lab so he can catch his so-called "impostor".
Meanwhile, Flippy the Mysterious Stranger was still up to no good. However, he didn't know that the treasure chests he stole from Penelope's Pets were actually made out of plastic, until he tries to pay them at Kinney's real estate. The owner explained to him that treasure chests are made out of wood and filled with gold. Just then, both of them noticed on television that Petey the Cat on his Treasure Tank 2000 was hypnotizing people with his love ray to take everyone's money. The Mysterious Stranger decided to go and steal it, whereas the owner declined. The stranger grew mad and used his mind powers to send the owner away.
Dog Man shows up with Sarah, Zuzu, and Chief, just in time to see Petey, Flat Petey (the other main antagonist) and the Mysterious Stranger (Flippy) arguing over the Treasure Tank 2000. Petey is chased back to Cat Jail as Flippy reveals who he is. As he was about to go and steal the Treasure Tank 2000, Flat Petey and the hypnotized Doctor Feeva had already escaped with it to the top of a snowy mountain while Flippy was speaking to Dog Man and the others. The evil fish chased Petey's paper clone out of rage, with Dog Man and everyone else following the villains to the top. Flippy freezes in his fish tank, but as Flat Petey sees Doctor Boog. E Feeva no longer useful and kicks him away, his belongings fall out of his bag. Flippy quickly reads one of the Witch Doctor's books and discovers how to live forever. Focusing his mind, Flippy's soul abandons his body and tries to possess Chief's body. Dog Man gets Flippy's soul in his mouth, and Flippy's soul slowly melts away. His empty body is left to freeze on the mountain when Dog Man, Zuzu, Sarah, Chief and Boog. E Feeva use Flat Petey's frozen body to sled down the mountain.
In Dog Man: A Tale of Two Kitties, Flippy's frozen body is recovered from the mountain by scientists to study his brain. He is brought back to life with metal parts and Living Spray, and he becomes Supa Mecha Flippy. He makes an army of Beastly Buildings and goes on an evil rampage in the city. Dog Man crushes all the Beastly Buildings with the help of Sarah, Zuzu, and Chief. Flippy becomes a good guy when Li'l Petey befriends him, and Flippy goes to Fish Jail for his crimes, but he and Li'l Petey make comics for each other and then he is happy.
In Dog Man: Fetch-22, he thanks to Li'l Petey's help got free from jail.
Trivia
- Flippy was not meant to be angry, it was the GR-2 in the Supa Brain Dots.
- Although Flippy's brain grew 11 times big, he wasn't always very smart at times, e.g. he mistook the plastic treasure chests from Penelope's Pets as actual treasure chests.
- For the first half of Dog Man: Unleashed, Flippy appeared to be the only main threat, until his position is shared with Flat Petey, who eventually became the true central antagonist of the book.
- Despite Flippy not being the true villain of Dog Man: Unleashed, he was the one who started the trouble in the city and was indirectly responsible for Petey's escape and Flat Petey's creation.
- In Dog Man: The Musical, he is played by Crystal Sha'nae (Original) and Jasmine Smith and Princess Sasha Victome (North American Tour).