Watch Grey’s Anatomy Season 6 Episode 4 (S06E04) – Tainted Obligation

Air Date: October 8, 2009 (10/8/09)
Title:”Tainted Obligation”

Tainted Obligation S06E04 Synopsis:

When Meredith and Lexie's father, Thatcher, returns to the hospital with a failed liver, it's up to Meredith to save his life. Meanwhile, Izzie empathizes with a patient riddled with tumors, as Mark, annoyed with Cristina's competitive zeal, tricks her into assisting on an unusual surgery.