Jenna and Cally bite

This 1978 ad over at vintage_ads really reminds me of Jenna and Cally. It's the hair of course, and after all 1978 was when Blake's 7 started. Pity the nerd doesn't look like Avon but there's no resemblance to anyone B7. I think Jenna and Cally are distracting him while they nick his suede jacket with the keys to the Central Control in a pocket.