The Round Trip Ticket is a twist featured in week 5 of Big Brother 18.
This twist was discovered by Paul Abrahamian when he cracked the code into entering the Secret Room. Within the Secret Room are twelve envelopes (one envelope for each houseguest). Paul was the first houseguest to discover these 12 secret envelopes. One of the twelve envelopes contains the Round Trip Ticket. The Ticket allows a houseguest to re-enter the house after they've been evicted. Houseguests are not allowed to open their envelope but instead hand them to Julie when evicted. Julie will open the ticket, and if it is a Round Trip Ticket, the houseguest will be able to return into the game. If the envelope is not a Round Trip ticket, then it is a "One Way" ticket which will send that evicted houseguest back home/to the Jury house. If a houseguest decides to open their envelope before eviction night, then that envelope will be void. The Round Trip Ticket twist will expire after four weeks of its appearance. After Paulie's eviction it was revealed that Paul had the round trip ticket.
"One Way Ticket"
"Round Trip Ticket"