I think Jeff's already turning, he wasn't amused by Shelly's behavior in the HOH room last night against Rachel. Then when he and Jordan were alone he praised Rachel for keeping quiet and trashed Shelly.

Shelly = Michele from BB11. She's going to drive Jeff nuts this week.

All Adam needs to do is spill on Shelly being the one to steal Rachel's stuff and Jeff would be done with her, which isn't a bad idea for Adam. It'll make him safer to keep for Jeff than Shelly.