Dr. Heinz Doofenshmirtz

Doctor Heinz Doofenshmirtz, also known as Dr. Doofenshmirtz or Doof is a fictional character from the cartoon television series Phineas and Ferb and its spin-off Milo Murphy's Law. He is played by Dan Povenmire.
Character
In Phineas and Ferb, Dr. Doofenshmirtz is an evil scientist who wants to use his machines to take over the Tri-State Area. He says he is "an evil scientist, not a mad scientist". His nemesis Perry the Platypus stops his evil plans every day. Dr. Doofenshmirtz also has a lot of bad luck and says the reason he loses every time is because he has "poor planning skills". Doofenshmirtz also gives almost every machine he builds a name ending with "inator". Even though he calls himself evil and is the villain of the show, he has some good wikt:traits. For instance, he really does love his daughter Vanessa.
Backstory
Dr. Doofenshmirtz likes to tell everyone his origin story to explain why he wants to try to be a supervillain. He says that neither of his parents showed up to the hospital the day he was born and that they never gave him a birthday party. He also says that his parents disowned him and he was raised by ocelots. Doofenshmirtz also says that when he was a child his only friend was a balloon that he lost and that his father made him stand all day in the lawn dressed up as a gnome. Doof also says his parents named their pet dog Only Son because Doofenshmirtz was scared to dive into a swimming pool and that his mother didn't let him go swimming in public pools and she liked his younger brother Roger Doofenshmirtz better than she liked him because Roger was the only one of the two who was good at kickball. Doof was also forced to wear dresses since his parents had thought Roger would be a girl. Dr. Doofenshmirtz says he hates Roger not only out of jealousy but also because Roger accidentally destroyed a painting that Doof made. Since he was a child, Heinz Doofenshmirtz was in many science fairs but every time he lost to a baking soda volcano. And when he became a writer of poetry, he still lost to a baking soda volcano. He faced a lot of bullies over time. A woman he liked left him for someone with big hands. After moving to America and getting married and later getting a divorce he had a girlfriend who left him for a whale.
Main Role in Phineas and Ferb
In almost every episode, Dr. Doofenshmirtz builds a machine called an inator either to get revenge on someone from a backstory or to take over the Tri-State Area and is beaten by Perry the Platypus. Even though he loses to Perry every time, Dr. Doofenshmirtz accidentally destroys whatever Phineas and Ferb built that day so that when their sister Candace tries to show it to their mother there is nothing there and Candace looks like she's crazy.
Redemption
In the second season of the show there was an episode called Summer Belongs to You where Dr. Doofenshmirtz works with Perry the Platypus to rescue his daughter Vanessa Doofenshmirtz. In the third season there was an episode called Agent Doof where Dr. Doofenshmirtz tries to become a secret agent working for the good guys and accidentally causes more problems than he did when he was evil so he decides to go back to being evil. In the Season Three episode, Where's Perry, Dr. Doofenshmirtz builds a machine called the "Ultimate Evil-Inator" to turn Perry's wikt:boss Major Monogram evil but accidentally hits Monogram's assistant Carl making him turn evil. So Doof ends up working with Monogram and Perry to stop Carl because Carl is a more dangerous villain than Doof was so Dr. Doofenshmirtz builds a machine called the Re-Good Inator and turns Carl good again. In the movie Phineas and Ferb: Across the Second Dimension, Dr. Doofenshmirtz goes to a parallel universe where a more evil version of himself already won and Doof ends up stopping the other him from taking over the Tri-State Area from the main universe. In the Season 4, episode Mission Marvel, Doofenshmirtz accidentally steals the powers of the superheroes from Marvel Comics and teams up with the Marvel supervillains but the villains betray him so Doofenshmirtz helps stop them. In the Season 4 episode Minor Monogram, Doofenshmirtz's sidekick betrays Dr. Doofenshmirtz and tries to take over the world so Doof helps stop him. In the Season Four episode, "Primal Perry" Dr. Doofenshmirtz hires a hunter from Australia named Liam to trap Perry the Platypus but ends up working with Perry to stop him after Liam tries to kill them both. In the episode Doof 101, it's revealed that after summer ended Dr. Doofenshmirtz was given a choice between jail and community service and ended up as a high school science teacher. And the episode Act Your Age set in the future reveals that Dr. Doofenshmirtz didn't commit any crimes since then. In the episode Phineas and Ferb save Summer, Dr. Doofenshmirtz helps the good guys stop a mad scientist named Rodney from putting the world in a new ice age but says he's still evil. In the horror episode Night of the Living Pharmacists, he accidentally starts a zombie pharmacist apocalypse and helps to stop it. In the series finale Last Day of Summer, he builds a machine called the Do-Over Inator so that he can start the same day over any number of times and accidentally nearly destroys the universe so he tries to save it from himself and his daughter Vanessa convinces him to turn good.
Spin-Offs
Dr. Doofenshmirtz appears in both episodes of the spin-off The OWCA Files in which he's partnered with Perry the Platypus and had to fight another evil scientist named Parenthesis. In the spin-off Milo Murphy's Law, Dr. Doofenshmirtz invents time travel and changes his name to Professor Time. Doof also appears in the movie Phineas and Ferb: Candace Against the Universe where he helps fight the aliens and save Earth.