Six years have passed, and Kingsbridge is busy with its Fleece Fair, but as tolls are collected on the creaking, rickety bridge, it slows access to visitors. Traders hawk their wares, Friar Murdo preaches hellfire and brimstone, and Petranilla isn't helping, just chatting with other merchants and making matters worse by refusing to haggle over prices.
Caris, now live-in student of Mattie the wise-woman, learns from Italian merchant Signor Caroli that the high prices and poor bridge access are driving custom away, and that an advertised witch-trial is just a cynical attraction to draw crowds. She summons Merthin from unpaid work at the cathedral to a meeting about the bridge with Edmund, Prior Anthony, Brothers Godwyn and Thomas - all knowing it should be wider, but none willing to foot the bill. The meeting fails.
Isabella appoints Earl Roland her tax-collector at Kingsbridge, where taxes are doubled as punishment for continued unrest against her, and he arrives at the market with members of his family, including his intended bride Margery and his sons William, married to Philippa, and Richard, Bishop of Kingsbridge. Ralph is with them, still a squire and infatuated with Philippa, but his clumsy attempts to pay courtly compliments are an embarrassment.
Ralph transfers his interest to Annet, a flirty peasant girl, but when that interest turns crude and blatant, her fiance Wulfric punches him out. Brawling with peasants doesn't improve Ralph's standing with Philippa. Meanwhile Prior Anthony is outraged by the new tax demands, claiming poverty - though later revealing that he, if not the Priory, is wealthy enough. Meanwhile King Edward challenges his mother's right to increase taxes for an unwanted war.
Lechery is also rife where Brother Godwyn is concerned, when he is distracted from spiritual matters by pretty Sister Mair. Venting to his mother Petranilla, he claims that the old rules of separation were best, but soon proves his own hypocrisy by trying to undress Caris as she sleeps. When she wakes and catches him he scurries away - in time to spy Bishop Richard having sex with Margery, his own father's betrothed.
When Gwenda arrives for the Fleece Fair, her first sight is Wulfric in the stocks. After an exchange that suggests future friendship, she pays for his release, only to encounter Joby and discover he has just sold her into marriage in exchange for a cow. Wulfric tries to defend her, but Brother Godwyn declares that such transactions are sanctioned in the Bible, and Gwenda is dragged off, a virtual slave. Her new 'husband' Sim is one of the local outlaws, and she's not just his wife but the common bedmate of the whole gang. When their leader claims precedence she plays along until she gets the chance to knife him, then flees back to Kingsbridge.
Before the witch-trial Roland announces the new taxes, but Ralph cleverly turns the crowd's protests into patriotic fervor, claiming that these taxes will pay for a war against the French whose blockade is causing all the problems at the Fleece Fair. Then the trial proceeds, and the accused witch is, inevitably, Mattie, with Brother Joseph her principal accuser.
Despite spirited defense from Caris, Mattie is sentenced to hang, and as she is dragged to the gallows on the bridge, Gwenda runs towards it from the far side with Sim in pursuit. That's when the weight of the execution mob does what's been threatening all along. The bridge collapses, pitching gallows and crowd into the river. Ralph rescues Roland; Wulfric saves Gwenda; Sim drowns; and Petranilla murders Prior Anthony to make way for her son Godwyn...