"NBC Experiment in Television" The Cube 1969

Synopsis:

An unnamed man, simply called "The Man" is trapped in a cubical white room where anyone else can enter and leave, but which he himself apparently cannot leave. A stool is brought in covered in strawberry jam, the furniture changes throughout the play. The main character, is subjected to an increasingly puzzling and frustrating series of encounters, as a variety of people come through various hidden doors. But, as many remind him, he can only leave through his own door, so he must find it to leave.

Directed by: Jim Henson
Written by: Jim Henson & Jerry Juhl
Runtime: 53 minutes
Cast:
Richard Schaal
Richard Schaal
The Man in the Cube 
Hugh Webster
Hugh Webster
Arnie 
Rex Sevenoaks
Rex Sevenoaks
Manager 
Jack Van Evera
Jack Van Evera
Prisoner 
John Granik
John Granik
Straight Man / Sergeant 
Guy Sanvido
Guy Sanvido
Comic Fritz