Harta’s eyes moved rhythmically from side to side. Even I felt the power of those deep brown eyes. The eyes that seemed disturbingly … human.

Eleven-year-old Esther has had enough of her annoying little brother, Rex.

But when Rex mysteriously swaps bodies with an orangutan called Harta, she winds up with a brother at the zoo and an ape in her bedroom.

It's up to Esther to help them switch back or risk losing Rex forever.