: Izzie and Cristina risk their careers to find the truth about a patient's death.
: Addison Montgomery-Shepherd arrives, revealing Derek is married.
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.
The episode ended on Meredith’s shocked face, leaving fans to wait months for the fallout of the revelation that "McDreamy" was actually a married man. Key Storylines from the Finale
The woman turned her gaze to Meredith, her eyes sharp. "And you must be the woman who's been sleeping with my husband."
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.
Watch a recap and review of the intense season 1 finale where secrets are finally brought to light:
: Derek operates on Chief Webber's brain tumor in secret.