During its return to the earth, commercial spaceship Nostromo intercepts a distress signal from a distant planet. When a three-member team of the crew discovers a chamber containing thousands of eggs on the planet, a creature inside one of the eggs attacks an explorer. The entire crew is unaware of the impending nightmare set to descend upon them when the alien parasite planted inside its unfortunate host is birthed.
A shiftless dreamer, Michael Rogers (Hywel Bennett) fantasizes about a lifestyle above his means and marries a wealthy, young girl, Ellie Thomsen (Hayley Mills) who just came of age. They hire a famous architect to build their dream home amidst a series of suspicious incidents. The spouse has dark intentions toward his naive, inexperienced bride. Secrets from his past and sinister ties to their houseguest Greta (Britt Ekland), lead to a terrible turn of unexpected events.
A dentist, Henry Morley, is found dead from a gunshot wound and the official verdict is that he has killed himself; a verdict apparently supported when it appears that he has given one of his patients a fatal overdose of anaesthetic. Is it suicide or was it murder? What happened in his surgery just before his death?
On receiving an inheritance from her grandfather, Canadian Jeannie MacLean decides to visit the family's Scottish roots. On the plane she meets businessman Stanley Smith, and romance blossoms in Edinburgh. The complications begin when Stanley breaks a date with Jeannie to woo voluptuous redhead Helene, and Jeannie is flattered by the attentions of the impoverished Lord McNairn; he's heard about her good fortune, and gallantly offers to show her the city.