from the back of the book:
Unknown to anyone, two creatures have wandered the Earth for generations. The aliens have no knowledge of each other, but share a residual memory of a mysterious, sunken relic -- and an affinity for deep water. One, the changeling, has survived by adaptation, taking the shapes of many different organisms. The other, the chameleon, has survived solely by destroying anything or anyone that threatens it.
Now, finally brought up from the bottom of the sea by marine biologist Russell Sutton, the relic calls to them both... to come home. For all these generations there have been two invincible creatures on Earth. But the chameleon has decided there's only room for one......
There is a Methodist connection -a mention of two stained glass windows in the Samoan Methodist church. There's also a mention of a character having met Arthur C. Clarke in the 70's. It wrapped up with what seemed to me to be undue speed, but nothing's perfect.
SFReviews calls it "high-concept entertainment that makes for the kind of popcorn page-turner" and "diverting beach novel that delivers a good read" while making note of several limitations.
But beneath all this—the comedy, the sprawl of backstories, the serpentine narrative—serious questions are broached. The problem of evil. How we learn. The foundations of ethics.