|“||Well, well, well... if it isn't C.O.W.C.A.'s best agent: the unfortunately named Lyla Lolliberry!||„|
|~ Bannister introducing himself to Lyla and Perry.|
|“||JINX YOU, LYLA LOLLIBERRY!! JINX YOU!!||„|
|~ Bannister after being caught and defeated.|
Professor Bannister is the main antagonist of the Phineas and Ferb episode "Sidetracked". He is an evil scientist who plans to annex Canada into Greenland, and is the arch-nemesis of C.O.W.C.A. Agent Lyla Lolliberry.
He was voiced by the guest star Kevin McDonald.
Despite being an evil scientist, Bannister comes up with a plan that even Dr. Doofenshmirtz thinks is implausible and enormously complex, even more than his own evil schemes. He has a strong love for his homeland Greenland and extreme jealousy towards Canada.
Bannister is originally from Greenland, but he grew sick of its national anthem and lack of national pride. His jealousy of Canada led him to plot his evil scheme there by posing as a Canadian evil scientist and building his own evil company Bannister Evil Enterprises. He also joined the villain organization L.O.V.E.M.U.F.F.I.N. (though it was against the rules for their members to misrepresent their countries of origin, as stated by Heinz Doofenshmirtz).
Bannister started off his plan by arranging three burglars to steal some parts from Seattle, which he uses to build two magnetic robotic versions of himself (known as Me-Positive & Me-Negative). Two months later, he plotted to steal Canada's symbol of national unity (Albert the Moose), knowing that it would sink Canada's national pride to a new low, which will allow him to annex Canada to Greenland and put in a new national anthem in order to reinvigorate its national pride to a peak. He even got Doofenshmirtz to assist him in his scheme as part of their U.S.-Canadian evil scheme exchange program, though Doof finds Bannister's scheme to be quite complicated in general. However, Bannister was found out by Lyla and Perry the Platypus, who were able to defeat his magnetic androids by using their magnetic fields against each other. Lyla and Perry then attempt to capture Bannister, but he uses the Greenland national flag to evade them. Bannister attempted to escape via parachute, but Perry managed to contact his old friend Peter the Panda, who managed to capture Bannister with his jet, much to Lyla's delight. In the end, Bannister and his cronies are arrested.
- Bannister's voice actor, Kevin McDonald, is known for his Canadian heritage, just like Lyla Lollibery's voice actor, Samantha Bee (who is also a Canadian).
- Bannister's final quote ("Jinx you, Lyla Lolliberry!") mirrors that of Doofenshmirtz's catchphrase ("Curse you, Perry the Platypus!").
- Bannister is considered one of the two members of L.O.V.E.M.U.F.F.I.N. sent to prison for life (the other is their leader Aloyse Von Roddenstein for his notorious attempt to send the Earth into a new Ice Age).