• 
  Benoît Allemane

   Grandfather (39 episodes, 2015)
• 
  Lucille Boudonnat

   Clara Sesemann (39 episodes, 2015)
• 
  Gabriel Bismuth

   Karl (39 episodes, 2015)
• 
  Jamie Croft

   Karl,Sebastian, Mr Keller (19 episodes, 2015)
• 
  Evelyne Grandjean

   Peter's Grandmother (39 episodes, 2015)
• 
  Thierry Kazazian

   Hans, Friedrich, Mister Traber (39 episodes, 2015)
• 
  Gilbert Levy

   Mister Keller (39 episodes, 2015)
• 
  Leslie Lipkins

   Theresa (39 episodes, 2015)

• 
  Julie Turin

   Dete (39 episodes, 2015)
• 
  Nathalie Homs

   Narrator (39 episodes, 2015)
• 
  Céline Ronté

   William (39 episodes, 2015)
• 
  Gilduin Tissier

   Sebastian (39 episodes, 2015)
• 
  Tess Meyer

   Narrator (39 episodes, 2015)
• 
  Monique Hore

   Heidi (39 episodes, 2015)
• 
  Thierry Gondet

   Mister Bakker (39 episodes, 2015)

• 
  Vanina Pradier

   Miss Rottenmeier (39 episodes, 2015)
• 
  Emmylou Homs

   Heidi (39 episodes, 2015)
• 
  Gabriel Bismuth

   Karl (39 episodes, 2015)
• 
  Laura Prats

   Heidi (in Spanish) (39 episodes, 2015-2017)
• 
  Nathalie Homs

  39 episodes, 2015-2017
• 
  Nicole Shostak

  26 episodes, 2015-2017