John Koyama

"Grey's Anatomy's" three-episode story arc continues with a part two that will challenge the interns of Seattle Grace -- and "Grey's" fans as well -- like never before.

Unassuming high school chemistry teacher Walter White (Bryan Cranston) discovers he has lung cancer. Desperate to secure his family's financial future and finally free from the fear that had always inhibited him, Walt teams up with a former student to turn a used RV into a mobile drug lab. Guest stars: Max Arciniega, John Koyama, Steven Michael Quezada Written by: Vince Gilligan Directed by: Vince Gilligan

Walt and Jesse (Aaron Paul) attempt to tie up loose ends. The desperate situation gets more complicated with the flip of a coin. Walt's wife, Skyler (Anna Gunn), becomes suspicious of Walt's strange behavior.

Rick Fox returns. A night of getting acquainted with her co-workers at Irv Smith Management leads to Tasha getting flashed by Lev, one of her co-workers who happens to be white. Meanwhile, Jason and Kelly attend marriage counseling sessions.

As Irina's trial nears, Sloane informs Sydney that Richter was infected by an Ebola-like virus that Sark has developed.