Doctor Who's River Song has got a tough time ahead of her — she's joining the biggest science fiction team of them all: the Legion of Formerly Mysterious Characters. Along with Darth Vader, the Man in Black and the Cigarette-Smoking Man, she'll dwell in a place where almost everybody knows all about her.

Almost every mysterious science fiction character eventually loses his or her mystery — unless they get cancelled first. But it doesn't have to be the end. Here are some science fiction and fantasy characters who lost their mystery, but managed to remain cool.

He claims to be just a simple tailor, working on Deep Space Nine — but we always suspect him of being somewhat more than that. Over time, we get more and more hints that Garak is actually a super-spy who's in exile for some reason. Eventually we learn that he's a former agent of the Obsidian Order who had a falling out with his mentor, Enabran Tain, and the gaps get filled in over time. But Garak never stops being an ultimate ruthless badass, who pushes his new Federation friends to do what must be done.

River Song's namesake is the central mystery of Joss Whedon's Firefly and Serenity. What did the Alliance and Blue Sun do to her? What superpowers does she actually have? And why is she so valuable to the Alliance that they're willing to kill anyone who's even seen her? We eventually find out all about River's past, her super-ninja powers and her connection to an atrocity that the Alliance wants to keep secret — but River? Still awesome and fascinating.

As usual, i will reproduce completely only the parts belonging to Summerverse.

Elim Garak from Star Trek: Deep Space Nine.

Ok, this one's not from the Summerverse but some of you are fans of Star Trek DSN, so...

To my great regret, Cameron is not on that list

Maybe he thought that Cam wasn't that mysterious?