Production of the episode was disrupted by the 1994 Northridge earthquake , which also affected the previous episode " Bart of Darkness " . The Film Roman building used by the staff was so badly damaged it had to be condemned . They were relocated to a new building for a year , and much of the animation for the episode was done by people at their own homes . The day after the earthquake , the only staff members who turned up for work were Bill Oakley and Josh Weinstein . Overall production of '' The Simpsons '' was disrupted for six months , with a month of production time being lost
1994 Northridge earthquake
1994 Northridge earthquake
Lisa's Rival