Revelation 11

One interesting prophecy received by John is concerning two prophets where the Lord -

"...will give power unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth.
4 These are the two olive trees, and the two candlesticks standing before the God of the earth.
5 And if any man will hurt them, fire proceedeth out of their mouth, and devoureth their enemies: and if any man will hurt them, he must in this manner be killed."  (New Testament | Revelation 11:3 - 5)

Apparently as olive trees (oil for preparation) and candlesticks (to bear light of Christ), they will be a great annoyance to Satan, his followers, and the wicked.  Joseph called these witnesses -

"...two prophets that are to be raised up to the Jewish nation in the last days, at the time of the restoration, and to prophesy to the Jews after they are gathered and have built the city of Jerusalem in the land of their fathers."  (Doctrine and Covenants | Section 77:15)

These prophets shall -

"...have power to shut heaven, that it rain not in the days of their prophecy: and have power over waters to turn them to blood, and to smite the earth with all plagues, as often as they will."  (New Testament | Revelation 11:6)

Again, an annoyance to the world. 

"And when they shall have finished their testimony, the beast that ascendeth out of the bottomless pit shall make war against them, and shall overcome them, and kill them.
8 And their dead bodies shall lie in the street of the great city, which spiritually is called Sodom and Egypt, where also our Lord was crucified.
9 And they of the people and kindreds and tongues and nations shall see their dead bodies three days and an half, and shall not suffer their dead bodies to be put in graves."  (New Testament | Revelation 11:7 - 9)

Obviously, the entire world will know of this event for -

"...they that dwell upon the earth shall rejoice over them, and make merry, and shall send gifts one to another; because these two prophets tormented them that dwelt on the earth."  (New Testament | Revelation 11:10)

And then -

"...after three days and an half the Spirit of life from God entered into them, and they stood upon their feet; and great fear fell upon them which saw them.
12 And they heard a great voice from heaven saying unto them, Come up hither. And they ascended up to heaven in a cloud; and their enemies beheld them.
13 And the same hour was there a great earthquake, and the tenth part of the city fell, and in the earthquake were slain of men seven thousand: and the remnant were affrighted, and gave glory to the God of heaven."  (New Testament | Revelation 11:11 - 13)

It is apparent they man of the wicked will be slain and some of the more righteous will repent.