Irrational Games creative director Ken Levine has provided an update on the status of BioShock Infinite's downloadable content.

"DLC Update: We are working on it--have been since the game shipped," Levine wrote on Twitter today. "Things are going well, but plz understand: game development takes time."

Asked if he could give any hints or release any screenshots, Levine said, "We can't until we can. Sorry."

The first DLC for BioShock Infinite is rumored to add a new AI companion character to the game.

BioShock Infinite's $20 DLC season pass includes three expansions for the first-person shooter, said to provide "hours" of additional gameplay and include new stories, characters, abilities, and weapons.

For more on BioShock Infinite, check out GameSpot's review.