For those new to Pretty Little Liars , introduces the core premise: One year after the mysterious disappearance of their queen bee friend Alison , four girls begin receiving threatening messages from someone named "A," who knows all their darkest secrets. Season 1 sets the foundation – the relationships, the lies, and the first clues about what really happened that night. Watching Season 1 in Spanish first is highly recommended before diving into the intense Season 4.