Delicate Ties - Trinity Masters: Secrets and Sins, #4

How far are they willing to go to catch a traitor? Going undercover at a club.a very specific kind of club.seems dangerous, but in a sexy way. Vincent doesn't normally teach people about the lifestyle he enjoys, but Christian and Charlotte each have their own roles to play in the investigation. Roles that include pretending to be his submissives as they search for a traitor. By day, architect Charlotte struggles to make sense of a coded blueprint of the tunnels beneath the Boston Public Library.
By night, the three lovers investigate the suspected enemy. Their tasks lead to earth-shaking discoveries. Not just about the evil surrounding them, but about themselves and their own hidden desires.