Yes, this was a movie too - but they took lots of liberties with the "based on a true story" and I wanted to read the nonfiction book it was based on.
It cannot be said that the Mee family "fell into" zoo keeping - it was a long, tumultous process fraught with challenges that eventually led to their owning the Dartmoor Zoological Park near Devon, England: they fought the former owner, creditors, banks and lending agencies, and even one another. Many people would have given up any number of times through the process but Benjamin persevered, even when his wife became gravely ill with brain cancer during the wind-up to licensing inspection.
Overall, this is a warm, personal story about a guy with a dream. The way the extended Mee family gets involved cannot be undervalued, and their commitment to the animals is amazing. The reader learns a lot about exotic animals, as incidents and anecdotes are sprinkled throughout the tale.