John McClane first encountered the 33rd floor when he opened the stairwell door to decide which areas he could hide from the terrorists in. He later went to the 33rd floor to rest when the SWAT team arrived. When the terrorists engaged the SWAT team, however, John McClane made an improvised bomb with Heinrich's C4 explosives, throwing them down the elevator shaft. It hit the second floor and caused all of their missiles to explode, killing James and Alexander and protecting the SWAT team.