UFO - Season 1 - Eps 10: The Square Triangle
"Unfortunately for them, an Alien came through that door instead of her husband." In the woods between Clare Cross and Lingbury, an injured Alien stumbles into a lonely cottage and is shot down by Liz Newton and her lover Cass Fowler. Liz and Cass are taken to SHADO HQ for questioning, but when Liz's husband arrives at the cottage, Paul Foster realises that the Alien's death was no accident!
About UFO

Title: UFO
First Air Date: 1970-09-16
Last Air Date: 1973-03-15
Status: Ended
Rating: 7.6/10 (from 45 votes)
Language: EN
Seasons: 2
Total Episodes: 26
Network: Associated Television
Genres: Sci-Fi & Fantasy, Drama, Action & Adventure
Production Companies: Century 21 Television, ITC Entertainment
Synopsis
A secret, high-technology international agency called SHADO defends Earth from alien invaders.
Cast

Ed Bishop
Cmdr. Ed Straker