Here's my definition of a great beach read - a fabulous story that sucks me in like a black hole and when it's over, it jettisons my bones across the galaxy with a hair on fire mission to convince everyone I know that they must read that book or they will die.
If you check back through human history, you will find that three things, more than any others, have produced social transformation: violence, knowledge and wealth - and the greatest of these is wealth!