When the enemies of Judah and Benjamin hear that they're building a new temple, they approach Zerubbabel and say they want to help since they've been sacrificing to God too.
Zerubbabel dismisses them, saying that the Israelites alone will build, since that's what Cyrus asked them to do. Anyway, it's not their place to join in the building.
But the enemies bribe the royal officials and successfully delay the temple rebuilding until the time of King Darius.
Before Darius comes to power, the enemies of Judah—Bishlam, Mithredath, and Tabeel—write a letter to the Emperor Artaxerxes, urging him to stop the rebuilding of the temple and the rest of the rebuilding projects in Judah.
Note: At this point, the original Hebrew changes to Aramaic.
Scribes named Rahum and Shimshai, on behalf of their associates (including, apparently, the Babylonians and the Persians in general, and the people exiled in the province "Beyond the River"), write another letter urging Artaxerxes to stop the rebuilding.
The letter claims that the Jews are rebuilding a wicked and rebellious city, Jerusalem.
If they're able to rebuild its walls, they'll stop paying tribute to the Emperor, and will go back to making trouble, causing the king to lose control of the whole province.
They tell Artaxerxes to look in the annals, where he'll see just how rebellious Jerusalem has been in the past.
Artaxerxes totally buys this argument and writes a letter back to Rehum and Shimshai, telling them that Jerusalem shouldn't be allowed to rebuild, since one of his officials looked into it for him and determined that the city had in fact been rebellious in the past.
Rehum, Shimshai, and their allies go to Jerusalem and stop the rebuilding projects by force. It won't be resumed until the second year of Darius' reign.