When three gorillas disappear, Dr. Grace McKenna stands to lose not only her livelihood and her professional reputation, but also three close friends, in this lively new novel by animal advocate and author Pamela Beason.

Grace, assisted by a crew of young advocates from the Animal Rights Union,  reluctantly fulfills a request from her project funders to hold a public exhibit of Neema, a mother gorilla, her baby Kanoni, and Neema’s giant, grumpy mate, Gumu. A dedicated cop, Matt Finn, supplies the project’s security protection (and Grace’s romantic interest).

After the public event,  the apes vanish, a huge pool of blood on the floor of the gorilla compound is “the only clue” to what might have happened. Did they escape into the wild?  Were they “liberated” by ARU operatives, or captured by exotic animal traders?

Grace can’t believe Neema would desert her, because the two have a close kinship based on their mutual use of sign language. Matt is sure someone connected with the project freed the gorillas on principle, or stole them for cash. He focuses on Tony Zyrnek, father of Jon, Grace’s most trusted assistant. Tony just got out of prison, is charming to a fault, and has a slew of highly questionable, greedy associates.

The project goes on lockdown, with Grace justifiably fearful of the consequences if word of the disappearance gets out. Matt and Grace are torn apart by the calamity, making it harder for both to function.

Matt’s investigations become increasingly complicated by crimes outside the compound, but his thorough police work gradually uncovers important evidence about the fate of the missing apes. Major revelations also result from Grace’s desperate delving into the bizarre international underworld where rare animals are bred and sold for profit.

Beason’s book, the second in her “Neema” series, will excite, enchant, and educate. Readers unaware of the innate intelligence of apes may be surprised to learn that Neema’s rather sophisticated communication abilities are based on verified fact. Beason skillfully shows us the human world through gorilla eyes.

Both dedicated animal rights proponents and people new to the dynamics of ape/human interaction will empathize with Gumu, Neema, and Kanoni’s struggles; while fans of the “locked room mystery” genre will fix their attention on the plight of the humans and their efforts to find more clues before it’s too late.

The Only Clue is a well-crafted mystery to inform as well as intrigue and captivate, opening an engaging realm of fictional exploration and speculation—the special bond that can happen between gorillas and people. Highly recommended.