As smoke began to escape the Zebra Room and drift down the hall toward other banquet rooms, patrons and employees nearest to the Zebra Room smelled it. The employees began to urge room occupants to leave the building. However, as the sprawling complex lacked an audible fire alarm, those in more isolated rooms had no way to know that there was a fire in the building until an employee walked the length of the building alerting them. Fire investigators later estimated that the fire, once it spread through the northern doors of the Zebra Room, took only two to five minutes to enter the Cabaret Room; as a result, news of the fire and the first of the smoke and flame reached the Cabaret Room, the farthest point from the Zebra Room, nearly simultaneously. By the time busboy Walter Bailey arrived in the Cabaret Room and interrupted the show to order an evacuation at 9:06 p.m., there was very little time left for the audience of around 1,000 people to leave via the room's small number of exits. As it spread laterally, the fire also began to spread upwards, engulfing the spiral staircase that would have provided the best exit for those on the second floor of the building.