A brutal survivor with few moral lines to cross. Joel, now in his late 57s,He lost friends, family and everything he valued, most notably his daughter Sarah, who died aged 12. 
4 years ago, Joel took Ellie on a dangerous journey to the fireflies, she was the cure for humanity, but she had to die. 
As he didn't want to lose another person again, he killed the doctors just to save her. He lied to her for 3 years, then told her the truth about it. Ellie then walked away and became angry with Joel. 