Hoshea is a bad king. Snore. When I've woken up, the Assyrians invade. He pays tribute to them, but one time he fucks up and sends a present to the Egyptian king but not the Assyrian king, so he gets locked up in prison. Yup, I like democracy better.
Assyria beseiges Israel for 3 years, then kidnaps all the Israelites and scatters them to the four winds. All of this, we are told, is punishment for worshipping Baal, and was explained back in Exodus, or Numbers or something, so they can't complain they weren't warned. Only Judah is left, even though they are no better at keeping the commandments.
As for the Assyrians, they take over Samaria, but when they don't respect god, he sends lions along to kill them. So they send for an old Israelite priest to come back and teach them god's ways. That satisfies him, even though they keep worshipping their own gods. The end.