Grayson Hawthorne always believed he was the heir apparent to his billionaire grandfather, but now Tobias Hawthorne is dead and his family disinherited. When Jameson Hawthorne's mysterious father comes to him looking for help to infiltrate London's most exclusive underground gambling club, which caters to the rich and powerful, Jameson reluctantly agrees. With the help of their brothers and the girl who inherited their grandfather's fortune, Grayson and Jameson both embark on different missions on opposite sides of the globe.