no saber de qué va la fiesta

Meanings:

• 1.

  SpainLatin Americaneutralliteral
  • To be unaware of the purpose, theme, or nature of a party or event.

• 2.

  SpainLatin AmericaGeneral Spanishcolloquialinformalfigurative
  • To be clueless about what is happening or what something is about; to have no understanding of the situation or the intentions behind it.