Answer: gatecrash

AnswerCrossword Clue
GATECRASHShow up without an invitation
GATECRASHAttend uninvited
GATECRASHEvade the ticket-taker
GATECRASHAttend without an invitation
gatecrashto attend a social event uninvited
gatecrasha person who enters, attends, or participates without ticket or invitation