Years before he died, Jeremy Fink’s father prepared a box containing “the meaning of life” for his son to open on his 13th birthday. When Jeremy receives the box a few months before that momentous day, the keys are missing, and it’s up to him and his best friend Lizzy to find a way into the box. The search for the keys—or, failing the keys, the meaning of life itself—takes the two throughout New York City and into a spot of trouble, which lands them a very unusual community-service sentence: They must return treasures to the children, now grown, who pawned them long ago. This device brings Jeremy and Lizzy—both originals to the core—into contact with a calculated variety of characters, all of whom have their own unique angles on the meaning of life. Mass spins a leisurely tale that’s occasionally Konigsburg-esque, carefully constructed to give narrator Jeremy ample time to reflect on his encounters. It may be a subplot or two in need of a trim, and the resolution will surprise nobody but Jeremy, but agreeable on the whole. (Fiction. 10-13)