MD80 Flight Attendant described an in-flight engine shutdown and uneventful divert.

Narrative

Normal flight. About 1 hour into flight; the Captain called the Flight Attendants about excessive noise to the left-hand engine. Asked us to go the back of the aircraft and report to him if the engine sounded 'louder than normal.' I didn't think so; but the #4 Flight Attendant did. Captain informed us he had to shut down that engine because of overpowering; possible overheating. He had us brief passengers on a planned emergency. We only had 20 minutes to landing and diverted to ZZZ. The #1 Flight Attendant read the Planned Emergency checklist to the passengers as I demonstrated to the passengers the Emergency Checklist. We only made it to; I believe; #6 on the checklist (made it to showing the brace position). Everyone watched and listened properly. #1 Flight Attendant was excellent on the PA and explained all of what was happening. We landed with no problem (a bit of a swaying back and forth before landing) but otherwise seemed somewhat normal. Deplaned and took another overnighted airplane. Agent was excellent helping us bringing catering from broken plane to new plane as it was late and the divert station had a skeleton crew. Pilots were great in communicating with passengers and crew. He explained on the PA what was happening. We took off from the divert station after about 1 1/2 hours (3 hours late).