At a crucial team gathering, Anna unexpectedly arrives to find Katie, the cheer captain, included in what she believed was her private celebration. Feeling betrayed by her longtime teammates choosing Katie over her, Anna confronts them fiercely, only to be pushed away and told to leave. The confrontation escalates as Anna struggles to understand why she was excluded despite their shared past. Meanwhile, chaos erupts when Katie suddenly collapses, and others panic as the severe side effects of an unknown cause take hold, leaving everyone desperate for help and the situation unresolved.