On a side note, Bellatrix LeStrange was played by Dumbledore, and Dumbledore was played by Mundungus Fletcher

Hagrid was also in on the scheme, being a member of the Order. Hagrid's role was to take out Professor M. so that they could bring her to the Evil Monkies, so when she went to St. Mungo's, they removed the real Prof. and switched it with Sturgis Podmore, so the real Sturgis Podmore was played by Sirius. Therefore, they didn't send Sirius through the veil, but instead they sent Lupin.

So the real Lupin was played by Mrs. Weasley, vut Mrs. Weasley was a blood traitor and while they weren't looking he replaced Sirius (who was being played by Lupin) with Sturgis Pdomre, who was actually being played by Sirius. You see, Mrs. Weasley did that because she wanted to date Lupin (who was being played by the real Arthur Weasley). So, Mrs. Weasley is actually a whore.

Oh, and the Ministry was actually helping the Death Eaters stop the Evil Monkies. Why else would they want Dumbledore and anyone close to him removed?