Eps9greys Anatomy - Season 1 -

While the interns gossiped about the outbreak, Izzie and Cristina were caught in their own ethical storm. They performed an unauthorized autopsy on a patient to prove his death wasn't their fault, eventually discovering a genetic condition that saved the man's daughter. Meanwhile, Derek was busy performing a secret surgery on Chief Webber, who was struggling with a brain tumor that threatened his eyesight.

As the shift ended, a heavy Seattle rain began to fall. Meredith and Derek stood near the hospital entrance, ready to head home together. Their conversation was light, filled with the easy intimacy of a couple falling in love. But the doors swung open, and a woman in a perfectly tailored coat walked in. She was striking, confident, and carried an air of authority that stopped them both cold. "Derek," she said, her voice steady.

: Izzie and Cristina risk their careers to find the truth about a patient's death. Eps9Greys Anatomy - Season 1

Watch a recap and review of the intense season 1 finale where secrets are finally brought to light:

The season one finale of Grey's Anatomy , titled "Who's Zoomin' Who?," originally aired on May 22, 2005. The episode is famous for its massive cliffhanger: the arrival of Addison Montgomery, Derek’s secret wife. While the interns gossiped about the outbreak, Izzie

Meredith Grey spent the day feeling like her relationship with Derek Shepherd was finally on solid ground. They had survived the initial awkwardness of their secret romance and the pressures of the internship. But at Seattle Grace Hospital, peace was always temporary. A syphilis outbreak had swept through the staff, forcing the Chief to hold a mandatory—and humiliating—meeting about sexual health. George O’Malley was the most public victim of the "syphilis train," having contracted it from Olivia, the nurse who had caught it from Alex Karev.

The woman turned her gaze to Meredith, her eyes sharp. "And you must be the woman who's been sleeping with my husband." As the shift ended, a heavy Seattle rain began to fall

: Derek operates on Chief Webber's brain tumor in secret.