10 Sci-Fi TV Show Mysteries That Can Never Be Solved

10. Annie (Lost)

More than ten years after it finished, there are still questions being asked about Lost. So let's just focus on one small mystery: Annie. Annie appeared in only one episode (The Man Behind The Curtain) in the flashbacks for Benjamin Linus.

Ben's backstory was compelling, he arrived on the mysterious island with his alcoholic father in 1973 and was miserable. His only friend was Annie, a small girl that arrived around the same time. Unlike his father, Annie remembered Ben's birthday and gave him a small doll of herself. After that, we never saw Annie again.

What happened to her?

We know that Ben kept hold of that doll, tenderly referring to it as 'a birthday present' when asked about it. But she didn't appear to be amongst the Dharma Initiative folks that were killed by the Others in 1992. Ben made a point of closing Horace Goodspeed's eyes, but didn't seek out Annie. So had she left the island by then?

Some speculated that Annie would turn out to be Kate (since she had used the alias Annie while on the run), but this was not the case. While Lost had so many unanswered questions, Annie remains one of the most intriguing. Indeed, actor Michael Emerson said that Annie's absence from the rest of the show was a missed opportunity.