May 6-24, 2020, you can view the new Third Wave documentary “The Invisible Line” streaming worldwide online at DOK.fest Munich Film Festival (German or English). Interviews with the original teacher Ron Jones, his wife, and seven students. The History Channel and Emanuel Rotstein did a great job! (Mark is Associate Producer, and interviewed in the film)
https://programme.dokfest-muenchen.de/de_DE/dokfest-films/14248

Mark and Director Emanuel Rotstein were also interviewed by DOK.fest:
https://www.youtube.com/watch?v=QpL_hqDwCPc