Dr. Smith, Will and the Robot encounter an alien being dressed as a medieval knight. The alien induces Will to become his page and Smith to be his varlet. Will is interested in the knight’s story, but Smith is motivated by the hope of passage back to earth in the alien’s spacecraft. The knight explains that he, Sir Sagramonte, has been on a quest to destroy the dragon Gundemar for uncounted years.
The next morning Sagramonte goes off alone in search of Gundemar. Meanwhile, Dr. Smith, having learned that Sagramonte has no ship, leaves for the Jupiter 2. On the way he encounters Gundemar. His screams are heard by Sagramonte who runs to find his beast. When Will becomes worried, he searches for the knight. His earlier doubts of Sagramonte’s ability are confirmed when he finds him addled and fretful, and the boy deserts him.
Penny herself later meets Gundemar and finds out that she is in fact a cultured and refined lady. The dragon tells Penny how distraught she has become by years of flight from Sagramonte. Penny resolves to help her and hides her in a cave. Unbeknownst to her, the whole episode is witnessed by Dr. Smith.
After Will has returned home, everyone notices how depressed he has become. He has lost faith in adults and no longer believes that there are any heroes to look up to. Dr. Smith feels sorry for him and goes to Sagramonte to convince him to restore Will’s faith by confronting Gundemar, and tells the knight where to find her. He then returns to camp and fetches Will to witness the combat. Penny overhears and rushes to help her friend Gundemar.
Penny is able to stop the fight between Sagramonte and Gundemar, and it is revealed that the dragon was responsible for instigating the quest in the first place; in fact, she has been teleporting herself and Sagramonte from world to world for many years. On hearing this, Sagramonte becomes utterly despondent, thinking he is a fool and has wasted his life; Will is even more depressed at the whole fiction Gundemar has perpetrated. Penny intercedes with Gundemar, who then provokes Sagramonte to the point where his old gusto is restored and his quest is renewed. The knight and his beast then disappear, teleported to a new planet, and Will’s faith in the heroic is restored.
GUY WILLIAMS ..as Professor John Robinson
JUNE LOCKHART ...as Maureen Robinson
MARK GODDARD ...as Don West
MARTA KRISTEN ...as Judy Robinson
BILLY MUMY ...as Will Robinson
ANGELA CARTWRIGHT ...as Penny Robinson
JONATHAN HARRIS ...as Dr. Zachary Smith
HANS CONRIED ...as Sagramonte
Story Editor... ANTHONY WILSON
Associate Producer... WILLIAM FARALLA
Music... CYRIL MOCKRIDGE
Music Supervision... LIONEL NEWMAN
Production Supervisor... JACK SONNTAG
Production Associate... HAL HERMAN
Unit Production Manager... TED BUTCHER
Director of Photography... FRANK CARSON
Post Production Supervisor... GEORGE E. SWINK
Art Directors... JACK MARTIN SMITH ROBERT KINOSHITA
Set Decoration... WALTER M. SCOTT JAMES HASSINGER
Costumes Designed by... PAUL ZASTUPNEVICH
Film Editor... FREDERIC BARATTA
Special Photographic Effects... L. B. ABBOTT, A.S.C.
Make-Up Supervision... BEN NYE
Hair Styling Supervision... MARGARET DONOVAN
Production Coordinator... LES WARNER
Supervising Sound Effects Editor... DON HALL, JR.
Sound Effects Editor... FRANK WHITE
Theme... JOHNNY WILLIAMS
Executive in Charge of Production for VAN BERNARD GUY DELLA CIOPPA
Color by DE LUXE
Copyright c. MCMLXVII SPACE PRODUCTIONS TWENTIETH CENTURY-FOX TELEVISION, INC. All Rights Reserved
Assistant Director..GIL MANDELIK
Supervising Music Editor... LEONARD A. ENGEL
Music Editor....JOSEPH RUBY
Post Production Coordinator... ROBERT MINTZ
Astronomical Photographs Copyrighted 1959 by THE CALIFORNIA INSTITUTE OF TECHNOLOGY
AN IRWIN ALLEN PRODUCTION in association with JODI PRODUCTIONS, INC. VAN BERNARD PRODUCTIONS, INC. TWENTIETH CENTURY-FOX TELEVISION, INC. & CBS TELEVISION NETWORK
WILLIAM SELF In Charge of Production
Filmed at the Hollywood Studios of TWENTIETH CENTURY-FOX TELEVISION, INC.
- Hans Conried and June Foray had worked before on "The Rocky and Bullwinkle Show" where Conried was the voice of Snidely Whiplash and Foray was the voice of Nell Fenwick, Rocky the Flying Squirrel, and Natasha Fatale.
- Is the Questing Beast happy or sad to be chased by the knight? When Penny first met her, the dragon was weeping, saying she was mortally afraid of what Sir Sacramonte would do to her, and only wanted to be left alone. However, later she reveals that she was the one who cast the enchantment that allows the knight to track her from world to world, giving him the means to keep following. Why would she have done such a thing if she was so afraid of him?
- Why did it take the Robot a whole day and a whole night to report to the Robinsons that Will and Smith had been taken prisoner?