Life with Derek is a half-hour comedy series about a modern blended family, with two type-A 15 year-olds, Casey (Ashley Leggat) and Derek (Michael Seater). Each episode is an alpha-teen comic war between two self-obsessed teenagers in a take-no-prisoners fight for control of their house, their school, and their world. On the fateful day when Nora McDonald (Joy Tanner) and George Venturi (John Ralston) decided to get married and merge their two families into one, there was a little detail they overlooked: they each had an individualist, controlling, sub-species of the human race â?? an eldest child. You really should not, on any account, have two of them in the same place. For Casey MacDonald and Derek Venturi, their own, genetic, siblings were never a real threat. But NOW? Two self-actualising, domineering eldest teenage children forced to co-habit the same house? The situation could be compared to having two north poles, two captains of the same ship, two alpha dogs in the same wolf pack.