Amid the desolation they discover a city... inhabited by cruel machines called Daleks. The Daleks hold a vital part of the TARDIS which means Dr Who and company can't escape. They encounter the Thals led by Alydon (Barry Ingham) and team up to defeat the Daleks and save what is left of the Thals' world...
An enjoyable science-fiction romp, unfortunately a little comedy was added to lighten the tone (not that it really needed it and this usually falls quite flat). As a straight forward Dr Who adventure it works pretty well, lacking much of the wit of the canon Dr Who but retaining some of the awe and fun and the slightly larger budget helps of course.