The first three seasons of Madison were set at Madison High School near Vancouver, British Columbia, and all three seasons covered one school year. The fourth season picked up six months after the end of the third, with the students beginning their lives outside of high-school.

The initial episodes centered on a different primary character each time, although before long the storylines were integrated into one another. Because of this initial individuality, there were no 'stars' for the first season as the cast changed with each episode.

Many controversial and hard-hitting issues were tackled in this drama, including inter-racial romance, teen pregnancy, abusive relationships, and losing parents and loved ones. Early episodes included the death of a classmate and the infant son of an interracial couple, and later on, the core group of friends lost one of their own in a tragic motorcycle accident, permanently changing the sister he left behind.