Andrew and Evie aren't initially sure what to make of the package
that arrives at their door soon after they move to a new town. It's
filled with random things--a key, something that looks like a kaleidoscope,
a seed packet, and a cryptic note. But over time, each item takes
on unique importance.
The twins decide to fill the dull weeks before the start of school
by spying on their neighbors. Their first target is their next-door-neighbor.
At first she seems like a run-of-the-mill older lady, but she turns
out to be a retired code specialist. She teaches them to create
and break codes, skills that become important as twins' search for
their mother intensifies.