throughout the Solarium scenes. Production Notes Johnny Byrne recalls that the original story idea featured a malevolent alien force (hence the previous title "Force of Evil"). During a story conference with executive producer Gerry Anderson, Byrne rethought the concept, with both men agreeing the entity should instead be following an evolutionary imperative unconnected to human emotion or understanding. To emphasise the truly alien aspect of the life-force, Bryne set the action against the very human domestic life of Anton and Eva Zoref. ITC executives insisted Byrne add the sequence where Koenig and Bergman speculate the entity's evolutionary cycle might be that of a developing star, hoping to provide some explanation for its actions. Byrne attributes the episode's success to the directorial style of David Tomblin. Tomblin would employ a number of unusual camera-angles and lens techniques to enhance the eerie quality inherent in the tale. After completing "Force of Life", Tomblin (one of three directors employed by the series on a rotating basis along with Ray Austin and Charles Crichton), would take a sabbatical from Space: 1999 to serve as assistant director for the feature film Barry Lyndon. He would be replaced for three installments by director Bob Kellett. This episode was taken to task by critics who accused Space: 1999 of being poorly plotted and/or deliberately enigmatic. While appearing on an American news programme, Martin Landau was confronted by a fellow guest personality, actor Buster Crabbe (star of the 1930s Flash Gordon and Buck Rogers serials). Having watched "Force of Life" and not understood the story, Crabbe demanded Landau explain what the alien force represented; to the delight of the series' detractors, Landau responded he had no idea. Novelisation The episode was adapted in the third Year One Space: 1999 novel The Space Guardians by Brian Ball, published in 1975. Ball's adaptation is true to the story, but some liberties are taken: (1) Suffering from a bout of depression, Koenig has become a recluse after his experience on Zenno (as seen in "Missing Link"). He is seen convalescing in his quarters and experiencing migraine when thinking of his lost love Vana. This crisis eventually forces him out of his fugue state; (2) The approaching entity does not employ a paralysing force in the adaptation. The Alphans attempt to blast it with nuclear missiles before it joins with the unfortunate Zoref; (3) While harbouring the entity, Zoref undergoes a gradual