The photos below, taken by John from Canadagraphs, are pretty spoilery, in as much as they reveal a future guest star for Supernatural. I can't predict with 100% accuracy, but I suspect that these photos are from episode 6.11, though I might be off by one episode number either way.
Guess who's making a return appearance in season 6 of Supernatural? None other than Lindsey McKeon, who plays Reaper Tessa. Tessa was first spotted on the show back in the season 2 premiere episode "In My Time of Dying", when she tried to reap Dean after the Winchester boys were in the accident. As fans will recall, Tessa's attempts were ultimately thwarted by the Yellow Eyed Demon, who made a deal with John to spare Dean's life in exchange for his father's.
Tessa was later spotted again in the season 4 episode "Death Takes a Holiday". In that episode people were unable to die because reapers had been rendered powerless in a little town due to kidnapping. Dean and Sam went to investigate and found Tessa there. She was ultimately taken by Alastair to use in a ritual to break a seal, but Alastair was captured by the angels and Tessa went back to reaping. We haven't seen her since then, but it looks like we'll be getting a blast from the past when Tessa shows up again in a future episode in season 6.
Why could Tessa be back and meeting up with Dean again? Will she provide him with information regarding the alphas that keep popping up this season? So far Tessa has proven herself pretty calm, despite her profession, and seems to have a soft spot for Dean. It will be interesting to see how they work her into the storyline again.
You can view some on-set photos below from Canadagraphs. You can also head over to that site for a few additional photos of Jensen and John's report of his experience around the set.
http://tvovermind.zap2it.com/cable/thecw/supernatural-tv-news/supernatural-set-photos-spoilers-guess/37423