Helaman and his army gather outside of Manti. They are spotted by the Lamanites.
Two portions of Helaman’s army, lead by Gid and Teomner hide in two different places.
The Lamanites chace Helaman without noticing Gid and Teomner.
Gid and Teomner capture Manti easily anfter the Lamanite have left. The Lamanites continue chasing Helaman towards Zarahemla.
The Lamanites are afraid because Zarahemla is too big of a city for them to take without being destroyed. They turn around and pitch their tents as night falls. Helaman passes them in the dark, going back to Mani.
Helaman arries in Mani with the rest of his army. The Lamanites awaken and also arrive.
The Lamanites are surprised that so many Nephites are in their city. They flee.
The one thing that doesn’t make much sense at first is this verse:
And behold, now it came to pass that our next object was to obtain the city of Manti; but behold, there was no way that we could lead them out of the city by our small bands. For behold, they remembered that which we had hitherto done; therefore we could not decoy them away from their strongholds.Alma 58:1
So this says that they weren’t dumb enough to let the Nephites take it while they were gone, but that is what happened! My guess is that after they found Helaman, they searched all around the city to make sure nobody else was there, and Gid and Teomner didn’t separate from Helaman until after they searched.