The black bull broke from the pack seconds into the 875-metre dash, shouldering through the crush of white-clad runners and slamming a horn into the side of a woman’s face. She was one of thirteen people treated by medics that morning, her wound the most graphic in a run that left cobblestones slick and bodies heaped in stumbling pile-ups. Many runners appeared oblivious, shoved aside by bulls that seemed more intent on clearing a path than goring, as the animals thundered from the pen to the ring where they would be killed later that day.

As the bulls charged, another American was making a different kind of spectacle. Lacey Mrzena, a young man from the United States known on social media as the ‘Joker’ for his purple-suited costume, was filmed holding a mobile phone and touching one of the animals mid-run. Argentine media reported that municipal police later intercepted him in the plaza and imposed a sanction; local ordinances allow fines of up to €6,000 for using a phone during the encierro. It was not his first brush with danger: days earlier, a heifer had tossed him in the ring before thousands of spectators.

The fifth run of the 2025 San Fermín festival unfolded in the long shadow of Ernest Hemingway, whose novel The Sun Also Rises was published a century ago and transformed the Pamplona fiesta into a global pilgrimage. Americans now form the largest contingent of foreign runners—16 per cent in 2022, according to city hall figures, four times the number from neighbouring France. Bill Hillmann, a 44-year-old from Chicago who has been gored three times and has run with bulls hundreds of times across Spain, told reporters that reading Hemingway at nineteen had set him on a path to become both a writer and a bull runner. “By the time I was done with that book, I was going to be a writer and I was going to be a bull runner,” he said, gazing down at the holding pen.

The bulls that charged that morning—from the José Escolar ranch—were later fought in the afternoon corrida, and Spanish critics were scathing about their temperament. One review described the animals as “prehistoric” and “carnivorous,” lacking any hint of bravery or noble caste, and noted that the matadors became “heroes just for pushing forward.” The Colombian Juan de Castilla was violently tossed, suffering a fractured foot, while the Mexican Isaac Fonseca managed to cut an ear from the sixth bull in what was deemed an act of sheer valour. The same black bull that had gored the woman in the face earlier had, according to the critic, fled to the boards “like a shot” when it felt the steel of the sword—a final, skittish image of an animal that had been, for a few frantic minutes, an unstoppable force on the streets.