The Princess Bulma is Bulma's cruise liner and it is the location for Bulma's birthday party.
After Bulma and Vegeta, along with their son, Trunks, stay at a resort during their family vacation, Bulma decides to host her birthday party on a luxury cruise ship. Trunks shows Goten around the ship, upon which they find a room with a plane, car, and a huge diamond, which Trunks says are the bingo prizes. Trunks pushes a switch, and a stand with all seven Dragon Balls, which are locked-up and heavily protected, rises up from the floor. Meanwhile, Emperor Pilaf, Mai, and Shu are stranded and fishing for food, until Pilaf's Dragon Radar starts beeping, signaling the Dragon Balls are nearby, which, to their excitement, is on the ship close to them. As everyone is enjoying themselves, Vegeta is contacted by King Kai via telepathy, who explains that Beerus and Whis are visiting Earth, looking for the Super Saiyan God. Vegeta is warned to not anger Beerus at all costs, or the Earth will be destroyed. During their visit, Beerus is bombarded with accident after accident, to Vegeta's apprehensiveness that Beerus will be set off. Soon enough, Beerus finally gets set off after Majin Buu doesn't share any pudding with him. The two duke it out, with Beerus severely overwhelming Buu. Gotenks, Piccolo, Android 18, Tien Shinhan, and Gohan all fall victim to Beerus, as well. Bulma, upset with Beerus for ruining her party, slaps him. Unaffected, Beerus back-hand slaps her, causing her to get knocked away from the force of it.
Vegeta becomes enraged, turning Super Saiyan 2, and charging after Beerus, connecting a few punches in the process, before becoming fatigued and losing to Beerus like the others. During these turn of events, Whis is completely oblivious to what is happening, as he is too busy eating the delicacies offered by the chef. Then, Beerus and Oolong have a rock-paper-scissors contest to decide the fate of the earth. After Oolong loses, Beerus decides that he will destroy Earth, and charges a Sphere of Destruction from the tip of his finger. Before Beerus has the chance to finish off Earth, Goku arrives and asks Beerus for more time. After his plead is granted, Goku and friends gather the Dragon Balls and summon shenron, to whom they ask how to become a Super Saiyan God. After Shenron explains and disappears, they perform the ritual. After a long and tedious process, Goku finally becomes a Super Saiyan God and challenges Beerus to another fight. After Goku is defeated, he falls down to Earth where he's caught by Vegeta before he can hit the ground. Beerus returns to the ship, who seems ready to finally destroy Earth.
Goku intervenes, begging him to stop, but Beerus ignores him. He charges a purplish ki-blast and releases it, but falls asleep, causing himself to miss. Whis thanks Goku for playing with Beerus and asks them to have an abundant amount of pudding the next time they visit Earth. Bulma anxiously awaits for them to leave, and after they leave, Goku chows down on a meal. He is informed by Gohan that he and Videl are having a baby. Nervous at first, Gohan is surprised to hear Goku tell him to eat lots of food. Goku offers Vegeta a chance to become a Super Saiyan God like he promised, but Vegeta shrugs it off, saying that he'll earn the powers of Super Saiyan God on his own.