This is not a good sign for FlashForward.

Over a month away from its return to ABC, the mysterious drama has lost its best-known creator and producer: David S. Goyer, who wrote Batman Begins, is stepping aside.

The series premiered to decent ratings, but tailed off once it failed to establish interesting characters and could never make much sense of its enormous, globe-encompassing plot. 

Goyer will still be "involved" in the show, sources say, even retaining an executive producer credit. However, he will not pen any episodes or be involved in day-to-day operations.

This makes the second behind-the-scenes shake-up on the show. In October, Mark Guggenheim also exited as a writer/producer.

FlashForward returns on March 18.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.