20 Things You Somehow Missed In Alien
7. The Telltale Legs
What makes the trousers flub in this scene worse - and what makes the scene in general infinitely more horrifying - is that when Ripley finally arrives on the scene Lambert is no longer wearing them. In fact, from what can be seen of her hanging remains, she's not wearing anything at all.
The sexual undertones of Alien have been documented and debated since the movie was released, but without stating it directly the implication here is that, prior to killing her, the creature violated Lambert in some capacity.