The episode begins with Bluey eating in the sitting room, when Bingo bursts in and suggests playing “Ground’s Lava”. Bluey agrees, but first, she needs to put her plate in the kitchen. As she walks into the kitchen, she sees her parents, Chilli and Bandit, arguing about the bin. Bluey asks if they’re squabbling, and Chilli tells her to wait a moment. Bluey tries to intervene, telling them to stop squabbling, but Bandit says they’re just talking. Chilli reassures Bluey that everything is okay, and they’ll discuss it later. Bandit responds with sarcasm, saying he can’t wait.
The scene shifts to Bluey setting up a “letterbox” for her parents, giving them each a mailbox and some writing materials. She introduces herself as the postie and tells Bandit to write a letter to Chilli. Bandit is confused, but Bluey insists that he write that they’re not enemies. Bandit explains that they were just having a discussion, but Bluey thinks they were squabbling. Bandit finishes writing the letter, and Bluey takes it, riding her postie bike into the sitting room.
Bingo reminds Bluey that they’re playing “Ground’s Lava”, but Bluey has forgotten. Bingo gets sad, feeling that Bluey always promises to play with her but doesn’t follow through. The two start arguing, but then Bluey realizes they’re squabbling. She suggests they play both “Ground’s Lava” and “Postman” at the same time. Bingo agrees, and they continue their adventure, trying to reach the top deck to deliver the letter to Chilli.
As they navigate through the house, they encounter obstacles, including the “lava” stairs. Bluey decides to make the steps not lava, but Bingo disagrees. They start squabbling again, but then Bluey realizes what’s happening and suggests they use “stepping stones” to reach the top. They use books to climb up and eventually make it to the top deck.
However, they take too long, and Chilli is now lying in the yard, listening to music. Bluey is worried that she’ll never deliver the letter, and Bingo asks why it’s so important. Bluey explains that she thinks the letter will prevent her parents from being enemies forever. Bingo is shocked, and they start discussing why Bluey didn’t want to play “Ground’s Lava” initially. They both apologize for squabbling, and Bluey admits that it felt good.
The two remember the letter and decide to make a paper airplane to deliver it to Chilli. They follow the instructions in a book, folding and shaping the paper. After finishing, Bluey throws the plane, but it flies in the wrong direction. However, with the help of the wind, the plane changes course and reaches Chilli. She opens the plane, reads the letter, and smiles. Bandit looks at her, and the episode ends with Bluey and Bingo celebrating their successful delivery.
