This installment was originally published in Look and Learn issue no. 532 on 25 March 1972.
The Prisoner of Zerss (continued . . .)
This installment was originally published in Look and Learn issue no. 522 on 15 January 1972.
The Duplication Machine (continued . . .)
This installment was originally published in Look and Learn issue no. 504 on 11 September 1971.
