By this time, Harriet had led several expeditions south to rescue people, focusing on her relatives. However, when her husband John refuses to go with her, she leads other slaves to Philadelphia in an “unplanned, spur of the moment” (123) mission. In the following months, Harriet develops a “broader purpose” as she continues to enjoy the “great, incredible wonders of freedom” (124), which she wants all Black people to have. Though she wants to help end slavery by enabling runaways and making slave ownership unprofitable, she is also concerned about the Fugitive Slave Act.

Harriet hears stories that make her worry about the fate of runaway slaves. One is about a runaway named Shadrach who is captured in Boston and has to be smuggled to Canada to avoid recapture again. While he does escape, Harriet is alarmed that he faced the slave catchers’ violence even in Boston. Indeed, another fugitive slave named Thomas Sims is also recaptured in Boston and sent back to his slavemaster in Georgia, where he endures a brutal punishment. Harriet is upset by these developments and realizes that the next time she guides people north, she will have to take them over the border to Canada so they can be certain of their safety from slave catchers.