In the sequel to the original journey of Don Tillman and Rosie Jarman, their newest adventures take the reader on another rollicking ride.

Don is still a genetics professor and Rosie is working on her Ph.D. and getting ready to enter medical school.

Many unexpected events seemingly derail the two of them, but they are temporarily back on track when Don finds them a new apartment. His friend Gene’s marriage woes have led to him being a houseguest for a while.

In typical “Don fashion,” we see what happens to him after Rosie announces her pregnancy. He approaches it all like a scientific study, learning about pregnancy and parenthood. But some of his explorations have drastic consequences, and soon he is facing all kinds of problems.

What will Don do to extricate himself from the tricky situation in which he lands? How will he keep the secrets from Rosie, the ones he feels are necessary for her well-being? And what will a social worker named Lydia add to the mix?

There were times in this book that I was annoyed with Don’s inability to react “normally,” but I also found Rosie frustrating. The two of them seemed determined to destroy their marriage. What would finally change everything for them?

Another fascinating journey into the unique world of these characters, The Rosie Effect: A Novel was unputdownable. I give this one 4 stars, primarily because the journey could have been smoother for me, but others might love all the ins and outs of how Don approached everything.