Robert John Burke (Bart Bass) was recently spotted on the set of Gossip Girl.

Yes, Chuck Bass' father is returning to the CW drama this spring ... a significant event in that he's, you know, deceased. Burke appeared once before since Bart passed, as a ghost of sorts, or figment of Chuck's imagination (see pic below), however it's unclear what brings him back to his Upper East Side stomping grounds time around.

If we had to guess, however, we'd put our money on a flashback sequence.

There's plenty of potential material, given the mysterious, largely unexplored link between Diana Payne (Elizabeth Hurley) and Chuck's family, not to mention the return of Jack Bass (Desmond Harrington).

Jack's latest UES visit, as previewed in the sneak peek earlier this week, seems a little too devoid of scandal, doesn't it? This is just a hunch, but be on the lookout for a major Bass family history lesson.

In other show news ... there's this cryptic Gossip Girl spoiler.

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.