Dartmouth McKinnon-Graham is a character and the main antagonist of the Canadian Boys in-universe comedy/drama TV series Secondary School by the Sea.
Dartmouth is a 28-year-old teacher of White English Canadian heritage. He has brown hair and dark chocolate eyes. He usually wears a beige suit with a white-and-sky-blue striped tie and a white collared shirt underneath, and a pair of black laced shoes. He is nearly always seen carrying his suitcase in his left hand.
Dartmouth is pessimistic, always expecting things to take a turn for the worst or go horribly wrong - he never looks forward to teaching his students. He has a very violent bad habit of randomly hitting students - even well-behaved ones - with his suitcase, which has led to an ongoing 'campaign' by the entire student community of the school to have him killed. This often leads to him sustaining injuries, which are sometimes so severe that he needs to be hospitalized for a few days afterwards. Fortunately for Dartmouth, the students' attempts on his life always fail because of his good luck, but this is a double-edged sword for him as he has now developed chronic paranoia and having recurrent nightmares about being successfully killed as a result. Because of this, he secretly suffers, but his uncaring personality and cruel demeanour means he always hides it from others.
Dartmouth hates Jollimore, a fellow young teacher at the school, because of his concentration on the brighter side of life and his philosophy of always finding positives. He often calls Jollimore's outlook a "load of New Age malarkey" and keeps telling him to "wake up and smell the coffee", which Jollimore obviously ignores.
- Dartmouth is named for a city in the province of Nova Scotia, just across the harbour from Halifax, the capital. A popular nickname for the city is the "Darkside", apparently referring to its perceived lack of culture as opposed to Halifax, and possibly explaining his name and negative traits.
- Dartmouth's name is often used in the Canadian Boys universe as a way to frighten people, intended to make them think he is actually coming after them.