I like this author. His books are meaty and rich with interesting characters. He has a series I love - the John Corey series. I listen to audiobooks constantly, and I've been lucky to have one of my favorite narrators read this series throughout. It's about an ex-cop who is now an ATTF Special Agent that works with the FBI on various cases. He is utterly hilarious in his sarcasm and humorous quips, but he's also damn good at his job.
Most of the books involve John scrambling to stop evil-doers of hurting our country. The pacing is suspenseful where it needs to be and funny as you take your journeys with John and his assignments. I would suggest starting with the first one, "Plum Island."
DeMille has another series, though there are only two books thus far. It involves a different John...John Sutter. He's an attorney who gets wrangled into working cases involving the mob. These two are "The Gold Coast" and "The Gate House." Naturally, start with the first one, "The Gold Coast."