Meanings of nefarious deeds in English

Some of the rhymes tell us about the nefarious deeds of wicked Guy Fawkes, who

I'm telling you all about my nefarious deeds.

The young boy serves as his accomplice for his nefarious deeds, in a sort of depraved mentoring relationship.

Ssserek, of all creatures, knew them well, having met them at night as they crept about on their nefarious deeds.

Manuiloff, who had forged incriminating documents many times, and who had a dozen underlings who assisted him in these nefarious deeds, understood perfectly.