Victor Conte's path to the center of American sports was improbable. He had played bass in the funk band Tower of Power before reinventing himself as a nutritional scientist. In 1984, he founded BALCO in Burlingame, officially offering blood and urine analysis and food supplements. By 1988, he had maneuvered his way into the Olympics, offering free tests to a group of athletes he dubbed the BALCO Olympians. From there, his network grew methodically. In 1996, he began working with NFL star Bill Romanowski, who connected him to coaches and athletes across multiple sports. Conte co-founded the ZMA Track Club with coach Remi Korchemny, attracting sprinters Marion Jones and Tim Montgomery. In 2000, he reached Barry Bonds through personal trainer Greg Anderson, and the web expanded to include baseball's biggest stars.

The drug that made BALCO different was tetrahydrogestrinone, or THG -- nicknamed "the Clear" because it was invisible to every drug test in existence. Developed by chemist Patrick Arnold, THG was a designer steroid engineered specifically to evade detection. Athletes could use it with impunity, confident that no lab in the world could catch them. The scheme unraveled in June 2003 when U.S. sprint coach Trevor Graham, in an anonymous phone call to the United States Anti-Doping Agency, accused several athletes of doping and named Conte as the source. Graham delivered a syringe containing traces of THG. Dr. Don Catlin at UCLA then developed a test for the substance and found 20 positive results among 550 existing athlete samples.

On September 3, 2003, agents from the IRS, FDA, San Mateo Narcotics Task Force, and USADA raided BALCO's facilities. They found customer lists alongside containers labeled as steroids and growth hormones. A search of Greg Anderson's home two days later turned up steroids, $60,000 in cash, and detailed dosage plans. The client list read like an all-star roster: baseball players Barry Bonds, Benito Santiago, and Jeremy Giambi; sprinters Dwain Chambers, Marion Jones, and Kelli White; boxer Shane Mosley; NFL players including Bill Romanowski and Dana Stubblefield; swimmer Amy Van Dyken. Conte pleaded guilty to steroid distribution and money laundering in 2005 and spent four months in prison. Anderson served 13 months. Bonds was indicted for perjury and obstruction of justice; in 2011 a jury convicted him on one count of obstruction of justice while declaring a mistrial on the perjury counts. The obstruction conviction was overturned on appeal in 2015.

Journalists Lance Williams and Mark Fainaru-Wada broke the story wide open, conducting roughly 200 interviews and collecting over 1,000 documents for their 2006 book, Game of Shadows. They were threatened with jail for refusing to reveal their sources, and were only spared when attorney Troy Ellerman admitted to leaking the grand jury testimony. The BALCO scandal reshaped American sports, leading to stricter testing protocols, congressional hearings on steroids in baseball, and a permanent asterisk next to the records of athletes who were connected to the lab. The building in Burlingame is gone, but the questions it raised about performance, fairness, and the integrity of competition have never been fully answered.