Another villain attacked ninjago, and being insanely strong they found the secret base of the ninjas. It wasn't expected but they fought for some time until eventually the army got them disarmed. You're still on the way, since you were on a sidequest to get a forbidden spinjitsu scroll, and you're the only hope.

"Please.. where are you.." Lloyd thought as he looked around having a sword to his throat. Kai sighed giving up and having a defeated expression on his face, while Jay seemed afraid