Played by actor W. Earl Brown, Bill thankfully doesn't take too long to take off his mask. It seems he has some history with Joel, though this is only a brief snippet that smartly doesn't reveal any more than it ought to; just enough to grab our attention.
On the one hand, this was a great human moment, but I'm also strangely anxious to see more of the infected. At least we got to hear one of them.
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