Lucas (Chad Michael Murray) investigates Dan's (Paul Johansson) heart condition while Haley (Bethany Joy Galeotti) struggles with letting Dan into Jamie's (guest star Jackson Brundage) life.
Nathan (James Lafferty) urges Quentin (guest star Robbie Jones) to reinvent his game and Brooke (Sophia Bush) juggles her career with life as a new mother.
Peyton (Hilarie Burton) tries to assuage her guilt over Lucas' breakup, and Mouth (Lee Norris) gets a shot to be sports anchor.