In the opening sequence, as passing scenery floats and blurs across the horizon, Lee describes the visceral experience of hopping a train. Switch and Baby Girl enjoy the view through the door of an open boxcar. Jessica recounts the thrill of her first freight trip and asserts, "It changes your perspective completely." Her boyfriend, Dan, recalls, "I just absolutely fell in love with the lifestyle and with the trains and with the misery that accompanies it all."

Cutting between synch-sound interviews and train footage, the characters share their thoughts and insights. But, as their personal stories unfold, the rails recede into the background. We visit Lee's cozy forest home, meet his parents, and eventually follow him to a hobo gathering in Dunsmuir, CA. Jessica settles temporarily in San Francisco where we meet her friends, her mother, and her sister. Switch and Baby Girl retire from the rails in order to raise their son Isaiah.

The trainhoppers in "Catching Out" confront the tension between individual freedom and social conformity. Disenchanted with mainstream society, they value the camaraderie of alternative communities. Lee considers the indifference of crowds on the street, in contrast to the forest where, "People that drop by your home really want to see you and be there." Jessica compares her experience as a traveling punk with that of a young yuppie. When Switch and Baby Girl settle off the rails, they say they feel threatened living in society because they are not the norm.

"Catching Out" also juxtaposes the trainhoppers' adopted lifestyle against the materialism and consumerism of mainstream culture. Jessica says, "I don't feel a big stress over money." Lee describes himself as being voluntarily poverty-stricken. Switch feels more freedom than the average person because he doesn't have to worry about bills. Baby Girl explains, "You don't need the world. You need the basics, and the basics are food, air, shelter, and love."