“Kill Straker!” is episode seven of season one of UFO.
SHADO Control has lost a UFO. The lunar module with Foster and Captain Craig is returning to Earth. SID detects the UFO and MoonBase confirms this and launches interceptors. The UFO alters course for the lunar module and the interceptors won’t make contact. It could reach the lunar module, and Starker orders they increase their angle of re-entry. The UFO still reaches them and Foster and Craig are bathed in coloured lights as a voice tells them to kill Straker.
MoonBase picks something up and launches interceptors. They identify it as the lunar module.
Straker and Freeman speak to Foster on MoonBase; he seems off. The module was out of contact for 16 hours, because the transmission antenna got fried. Foster blames Straker for the too sharp angle which resulted in them bouncing off the atmosphere when they levelled out.
Straker and Freeman are talking; Straker wants more MoonBases. Foster joins them. Straker wants the MoonBases in case the UFOs mount a massed attack. Foster doesn’t think they can mount one. In private, he says Straker is empire-building and should place himself on furlough. With probably Foster in charge.
Later, Freeman tells Straker he should slap Foster back into line, before he leaves for Earth.
As Straker is sleeping, Craig comes into his quarters, planning to inject him with an air bubble. Straker wakes and Craig gets away. He gets some explosives and heads outside to blow up the base’s facilities, but his spacesuit has too little air and he fails.
Foster, on the other hand, first tries more subtle ways of undermining Straker, before trying to set things up to make himself look like the good guy. Both have been hypnotised by the UFOs.