like allen's previous series "lost in space" and "the time tunnel", the theme music was composed by john williams. as with "lost in space", williams composed two different themes (in this case one for each season). williams also scored the pilot episode "the crash", and was the third composer to be attached to the project – williams' work replaced a rejected score and theme by alexander courage; joseph mullendore composed a second theme that was also thrown out. mullendore later scored five episodes and courage did one, with other episodes scored by richard lasalle (seven episodes), leith stevens (five), harry geller (four), irving gertz, paul sawtell, and robert prince (one each).