A homeless man, identifying himself only as "Mister," enters the offices of the powerful Washington D.C. law firm Drake & Sweeney and takes many of the lawyers hostage while angrily demanding information about some kind of eviction that took place. Although he is eventually shot and killed by a police sniper, one of the hostages, an antitrust lawyer named Michael Brock, is concerned by what he has learned and feels compelled to investigate further.
Brock finds his way to the 14th Street Legal Clinic, where he meets Mordecai Green, an advocate for the homeless. Green, along with his abrasive but brilliant staff, work to provide legal help to the most downtrodden members of society. Brock discovers that Drake & Sweeney were involved in the sudden approval of a federal building project on the site of a condemned building that had been serving as rent-payment housing for formerly homeless families. These individuals were tenants and thus entitled to a full legal eviction/contestment process, but a senior Drake & Sweeney partner ignored this information because the firm had a large stake in ensuring the federal project start on time, and thus illegally evicted the tenants in the middle of winter, resulting in the death of a homeless family. Brock takes a confidential file, intending to copy it, but is quickly suspected of its theft.
Shocked by what he has found, Brock leaves Drake & Sweeney to take a poorly paid position with the 14th Street Legal Clinic, which works to protect the rights of the homeless. This leads to the severing of his links to his previous white collar life, as his already-dying marriage officially ends in an amicable divorce. Brock later becomes emotionally involved in the case of a woman named Ruby, whose drug addiction led to her losing custody of her son. He also meets a young homeless advocate named Megan and they start a relationship. As Drake & Sweeney comes after Brock with theft and malpractice allegations, the clinic files a lawsuit against the firm and its business partners. The firm makes a deal where Brock has his license temporarily suspended, while they settle for a large amount of money and fire the partner whose actions led to the young family's deaths.
Drake & Sweeney's head partner, deeply troubled by the events, offer mg to make his entire staff available for pro bono work to assist the clinic in fighting for the rights of homeless people. The book ends with Brock taking a short vacation with Megan and Ruby, and them reflecting on their lives.
