After circus performance, Mitka and Petka decide to call their dog Trezor “Chamberlain” as the dog is no less cuter than a circus pet called Chamberlain. Once Chamberlain brings a pack of newspapers to Mitka and Petka. They go out to the streets and sell them, the NEPmen are anxious to buy the papers with have news about Denikin and Kolchak. However, the children are arrested and sent to the children's home. They soon become members of the All-Union Pioneer Organization. Another time Chamberlain saves Mitka who doesn’t know how to swim. This incident earns the pet respect and the Pioneers decide to rename him. They believe their faithful pet cannot share a name with the Soviet Union’s great enemy, Chamebrlain, and call him “Loyal”, instead.