As a travel escort for seniors, Emily Andrew-Miceli has led her feisty Iowa clan all over the world. This time, they're off to see historic windmills, classic Rembrandts, and picturesque canals in Holland, if they can ever unplug from their smartphones, that is. Joining them is the high school class from Bangor, Maine, whose 50th reunion celebration goes south faster than a fallen Brussel sprout soufflé as old rivalries start heating up. Worse, Emily's...