Cartoon Network snuck in 4 new episodes of Adventure Time last Sunday. One covered where Jake went with the blue guy, one followed what Finn was up to while that was happening, a third had Jermaine show up at the tree house because Jake had been gone for 5 months (that's just in the first couple minutes), and in the last we got to see the latest goings on with Uncle Gumbald.
I didn't know that CN was going to run them, I just happened to be browsing through the schedule and spotted the 4 episodes listed.