This Is Us 3x4 Vietnam Season 3 Season 0 0 EpisodesSeason 1 18 EpisodesSeason 2 18 EpisodesSeason 3 18 EpisodesSeason 4 18 EpisodesSeason 5 15 Episodes 3x1 - Nine Bucks 3x2 - A Philadelphia Story 3x3 - Katie Girls 3x4 - Vietnam 3x5 - Toby 3x6 - Kamsahamnida 3x7 - Sometimes 3x8 - Six Thanksgivings 3x9 - The Beginning Is the End Is the Beginning 3x10 - The Last Seven Weeks 3x11 - Songbird Road (1) 3x12 - Songbird Road (2) 3x13 - Our Little Island Girl 3x14 - The Graduates 3x15 - The Waiting Room 3x16 - Don't Take My Sunshine Away 3x17 - R & B 3x18 - Her A young Jack makes a decision that will impact the course of his life.