UFO (1970)

S1E10 The Square Triangle

In the woods separating Clare Cross and Lingbury, an injured Alien unexpectedly enters a secluded cottage, only to be shot by Liz Newton and her partner Cass Fowler. Afterward, Liz and Cass find themselves at SHADO HQ for interrogation. Meanwhile, when Liz's husband, Paul Foster, arrives at the cottage, he quickly deduces that the Alien's demise wasn’t a mere coincidence!