Ralf Wolter

as Dr. Leo Dorn (archive footage) (uncredited)

as Willy Stronz

as Peter

as Self

as Charly

as Self

as Leo

as Sam Hawkens (voice) (26 episodes)

as Onkel Jakob

as Self (1 episode)

as Herbert (8 episodes)

as Opa Grünwald (6 episodes)

as Hein Tietje (2 episodes)

as Monk

as Paul Bölkoff (1 episode)

as Prof. Boris Smirnoff

as Rüdiger Mattes (1 episode)

as Don Giovanni

as Miraculix (voice)

as Dr. Rehberger (1 episode)

as Eckmüller (1 episode)