Complex sentence: Calendar Man had been occupying the Solomon Wayne Courthouse, trapping anyone who entered and killing them on the next holiday; just before the game begins, Two-Face and his minions capture the courthouse and lock Day in a cell in the basement.
Split into simpler sentences: Calendar Man had been occupying the Solomon Wayne Courthouse trapping anyone who entered and killing them on the next holiday. Just before the game begins, Two-Face and his minions capture the courthouse and lock Calendar Man in a cell in the basement.