Scaramouche: Hey Aku, Jack doesn't have his sword.
Aku: Really? TIME TO UNLEASH UNSPEAKABLE EVIL ON HIM!
Aku flies to find Jack
Samurai Jack: I knew that you knew that I knew if lost my sword, I would do everything in my power to prevent you from knowing that, thus making you think you can easily kill me after 50 years of waiting for me to die of old age and causing you depression, only for you know to come to find me thinking I don't have the sword, when I actually have the sword and ready to vanquish you once and for all!
to himself
Samurai Jack: actually that was a lie, but Aku doesn't know that so I'll just mess with him.

"People keep asking me if I'm back and I really haven't had an answer. But now, yeah, I'm thinking I'm back!"