At the beginning of the 1994–1995 school year, Barty Crouch Jr, impersonating Alastor Moody through the use of Polyjuice Potion, demonstrated the Unforgivable Curses to Harry Potter's class using three spiders. The first spider was placed under the Imperius Curse, and was made to dance and perform acrobatics. Everyone in class were laughing, especially when Crouch had it jump onto students, until he suggested it to commit suicidal acts, as well as putting the curse on them. The third spider was struck by the Killing Curse, and died instantly.