I spent a little time out back with Julius by himself, which is a bit surprising. First he was there, and none of the other cats decided to intrude.
As I came up, Julius went into his wriggle-worm mode for me and squirmed at my feet.
I sat down with him and he alternately sat in petting range or orbited me like a little planetoid. Then something caught his attention and he was in full on hunter mode. A moment later he was on top of the wall and trying to catch a sound or glimpse of whatever was happening.
A few minutes later the emergency was over and I got him to chase a straw. In true Julius ‘goes to 11’ style, here he bit off a bit of the straw and is trying to spit it out.
I doubt this will stop him from overdoing it again the next time, though.