I'd point you towards Broken Sword 2. It's very well written ,and it's somewhat akin to what playing a Dan Brown novel would be like. It's also pretty funny if you have a warped sense of humor.
If you want a taste of what the writing and humor is like Beneath A Steel Sky, and Lure of the Temptress are free on here, and are by the same developers as Broken Sword 2!
Hope this helps!