The Bobbsey Twins in a Great City is a children's novel by Laura Lee Hope, published in 1947. It is part of the "Bobbsey Twins" series and follows the adventures of the Bobbsey twins, Bert and Nan, and their younger siblings, Freddie and Flossie. In this story, the Bobbsey twins are visiting their cousins in the city, where they get to explore all the sights and sounds of a big metropolis. They visit museums, go to the theater, and even attend a fancy ball at a hotel. However, their visit takes an unexpected turn when they meet a young boy named Tony, who is in trouble with a gang of thieves. The Bobbsey twins decide to help Tony and soon find themselves embroiled in a dangerous adventure to bring the thieves to justice. Along the way, they encounter new friends and exciting challenges, including a thrilling chase scene through the city streets. Through their bravery and quick thinking, the Bobbsey twins are able to help Tony and put a stop to the thieves' schemes. They return home to their family with newfound confidence and a greater appreciation for the diversity and excitement of city life.