As the former best friend of series protagonist Rick Grimes (Andrew Lincoln), Shane Walsh was quite a character. And unless you've read the comics before watching the TV show, he's introduced in the best possible way; charming you into believing that he is going to be one of the secondary heroes. But as much as Jon Bernthal fooled you into believing he was a selfless, heroic character, it was not to be as Shane was on his way to madness. Shane's arc throughout The Walking Dead is built on betrayal, as the love affair he had with Rick's wife Lori during the zombie apocalypse slowly began to unravel. Though they both believed that Rick was dead, his eventual return to the Atlanta camp began Shane's twisted downward spiral into insanity, culminating in a harrowing showdown near Hershel's farm. Bernthal and Lincoln had great chemistry together, which made for some amazing scenes the two of them could play with, giving immense credibility to Shane's transformation from hero to villain.
