|Alias||Tyler, Death Doctor, The Demon|
|Japanese Name||Sakura Tougo (佐倉東吾)|
|Friends||Amy, Derek, Angie Leslie Sears|
Tyler Chase is a surgeon that works at Caduceus USA. He has a younger sister named Amy Chase. Despite being smart and kind-hearted, Tyler is extremely lazy and doesn't like to work very much. He was Adel Tulba's mentor when he was a student at Caduceus USA.
Although he appears to be nice, Tyler was once a "Death Doctor" (a doctor who practices euthanasia), but he changes his ways after Derek saves Amy from Deftera.
Tyler has known Derek from medical school, and often teases Derek for copying his answers on tests. Upon Derek's arrival at Caduceus, he stumbles upon a thesis written by Tyler on euthanasia. It was eventually discovered that Tyler was so distraught over Amy's suffering that he even considered euthanising her. After Derek successfully cures Amy, Tyler changes his ways, and Derek suggests that he rewrites his thesis to contribute to the betterment of medical treatments. He even appears to be a little chivalrous towards the female doctors when Professor Blackwell breaks into Hope Hospital.
In Under the Knife 2, he is known as 'The Demon', for he works his interns hard and is very strict with them, no matter what the circumstance, this was just to intimidate Adel though.