In the Black of Night (Jegulus Crime AU)

When it all began, James Potter saw the world in absolutes: light and dark, life and death, and good and evil. For him, being an FBI agent meant being the unequivocal hero, saving lives without question. Then he was assigned to Regulus Black, the epitome of moral ambiguity.
As Regulus navigates the dangerous world of crime and corruption, he grapples with his own moral compass, struggling to find the true meaning of the oath he swore to uphold. Will he be able to find the good in the world, or will he be consumed by the darkness he desires to combat?

Or the one where James Potter picks between love and the law.

Crossposted on Ao3 : @ShortyWolf20