After two women poison to death the blackmailer who has been tormenting them, they wind up at the house of a blind man whose eccentric guest believes he has built a working time machine. Soon, the blackmailer is back to torment them all.
Unfortunately the movie The Unknown is not yet available on HBO Max.
| Writing | Joseph Stefano | Writer |
| Production | Lou Morheim | Associate Producer |
| Sound | Dominic Frontiere | Music |
| Production | Joseph Stefano | Producer |
| Directing | Gerd Oswald | Director |
| Camera | Conrad L. Hall | Director of Photography |
| Production | Joseph Stefano | Executive Producer |
| Lighting | Lloyd Garnell | Electrician |
