"All Of A Sudden I Miss Everyone" is the twenty-first episode, and the season finale, of the fourth season of One Tree Hill and the 88th produced episode of the series. It aired on June 13, 2007. Dan must face the harsh consequences of his decision to murder Keith as Karen and Haley's pregnancies complicate the lives of Nathan and the graduating seniors of Tree Hill High. Lucas wrestles with his post-high school options, and Peyton and Brooke prepare to spend the summer in Los Angeles together.