Usually when the doorbell rings on Big Brother, there's a big surprise behind it. On the June 29 episode of Big Brother 19, it was Nicole, Big Brother 18's winner calling, and she was there facilitate the first Head Of Household competition.
Her arrival was a bit of the shock to the rest of the houseguests, especially Paul. As the first surprise in the first episode of the new season, Paul believed he would be the only returning cast member. But Nicole wasn't there to repeat her win. She came in wearing her Big Brother 18 crown to facilitate the first HOH competition. Bringing her back for this reason may have motivated some houseguests, since Nicole was the first HOH of Big Brother 18 and she continued her winning streak to walk away with the grand prize. On the other hand, having a champion and a runner-up in the house could have been intimidating too.
Eventually, Cody secured the coveted HOH status, leaving the rest of the houseguests besides Josh (who grabbed the golden apple and secured his safety) wondering what their fate will hold. After the June 28 episode elimination of Cameron, tensions were permeating throughout the house. And in this season, the house is filled with superfans who understand the rules of the Big Brother universe: everyone is a threat and it's every person for themselves.
While alliances are still forming, it's the conflicts that are taking up residence in the house. Josh has officially confronted Megan, and Cody may use his HOH status to take out Paul. The power of HOH can change anyone's game, but Cody has already had problems with several of th houseguests (except his "bros"), so it's unclear if he will wield his power wisely.
Nicole's arrival definitely threw everyone for a loop, and she left them with Cody, who doesn't seem to like anyone. If the doorbell rings at the Big Brother house, maybe the best option is to hide.