And the Day the Hour appears the criminals will be in despair. (30:12)

Almuntakhab Fi Tafsir Alquran Alkarim

And on the Day the Final Hour has come, the wicked shall despair of making an earnest supplication begging and imploring Allahs forgiveness

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(30:12) On that Day when the Hour will come to pass, *14 the criminals shall be dumbfounded. *15

And the Day the Hour appears the criminals will be in despair. meaning

*14) "The Hour": the Hour of returning to Allah and appearing before Him.
*15) The word iblas in the Text means to be dumbfounded on account of a sudden shock and despair, to be confounded on finding one-self in a hopeless situation, to stand aghast on finding no means of help and support. When this word is used for a culprit, it depicts a person who is caught red-handed, who then find no way to escape, nor expects to save himself by offering a plea in self-defense; therefore, he stands dumb and dejected and depressed.
One should also understand that "the criminals" here does not only imply those people, who have committed murders and thefts and robberies, etc. in the world, but all those who have rebelled against God, refused to accept the guidance and teachings of His Messengers, denied the accountability of the Hereafter, or lived heedless of it, and have been worshipping others than God in the world, or their own selves, whether or not, besides this basic deviation, they also committed those acts, which are commonly called crimes. Besides, it includes those people also, who in spite of believing in God and His Messengers and the Hereafter, have knowingly disobeyed their Lord and persisted in their rebellious conduct till the end. When these people will suddenly come back to life in the Hereafter, against their expectations, and will find that they are confronted with the second life, which they had denied, or ignored, in their life-activity in the world, they will stand dumbfounded as has been depicted in the words: yublisul-mujrimun.
 

And the Day the Hour appears the criminals will be in despair. meaning in Urdu

اور جب وہ ساعت برپا ہو گی اس دن مجرم ہَک دَک رہ جائیں گے