Oh, that wily Bad Robot.  It just can't get over 'LOST,' can it?  First Desmond Hume (Henry Ian Cusick) signed up for a limited engagement on the J.J. Abrams-produced sci-fi series, and now 'Fringe' is about to get 'LOST' all over again by bringing back one of the island's most mysterious inhabitants.

TV Guide reports that former 'LOST' and 'No Ordinary Family' star Rebecca Mader will venture off the island to join the cast of FOX's 'Fringe' for at least two episodes toward the end of the season.  Mader will interact largely with Olivia Dunham (Anna Torv) as "a strong, brave woman involved in a case linked to supervillain David Robert Jones."

Not only that, but the otherwise-secret character is expected to maintain some kind of emotional connection to Olivia, and the pair "may find out they have more in common then they first thought," says executive producer Jeff Pinkner.  The character will share scenes with Peter Bishop (Joshua Jackson) and Walter Bishop (Jon Noble) as well, though the producer clamped firmly shut at questions of whether or not Mader could be a love interest for Peter, or recur next season.  You know, if it doesn't get cancelled.

Mader, best remembered for her stint on 'LOST' as life-long Island resident and nose-bleeding anthropologist Charlotte Lewis, is herself an avid 'Fringe' fan.  Mader stated in an interview with TVLine that “I just want to be on it… This show just blows my socks off. When I meet people who haven’t seen it, I’m like, ‘What’s the matter with you?'"

In addition to possible interaction with Henry Ian Cusick's similarly-veiled character, Mader also re-joins former 'LOST' co-star Lance Reddick, who played the very Matthew Abbadon that recruited Mader's character to the Island.

What say you, 'Fringe' fans?  Does the latest 'LOST' alumni to visit the 'Fringe' files get your bunsens burning?  What are your theories on how season 4 will end?  Watch 'Fringe's return this Friday with 'A Short Story About Love,' and we just may get our answers in season 5!