<P> The premise of the series is that Buffy is the latest Slayer , a young woman endowed by mystical forces with superhuman powers to fight and defeat vampires , demons , and other evil forces in the fictional town of Sunnydale . Like every Slayer before her , she was chosen and informed of her destiny when she was 15 years old . Her mother is unaware of her daughter 's powers and responsibilities until Buffy is forced to tell her at the end of the second season of the television series . Although Joyce is shocked at this revelation , she recovers quickly and remains a source of stability for Buffy and Buffy 's small circle of friends who assist her , dubbed the Scooby Gang . Eventually Joyce is able to take Buffy 's dangerous demon - fighting in stride and even become proud and respectful of her daughter 's abilities . Her natural death from an illness in the fifth season forces Buffy to face becoming an adult . </P>
when does buffy tell her mom she 's the slayer
end of the second season of the television series