Ariel and Indya are the twin detectives of Vance and Vance.
They are successful. Also a bit pricey, but if you want a case solved, murderer found, dog, cat, Big Foot or Loch Ness. Go to them.
They have the edge over all other detectives because they have a secret. They can read each other. While not exactly telepathy, they can get enough images that the thoughts are pretty easy figure out.
After many years of reading each other, they found they can read other people. No secrets are safe with them.
They have only one case that they’ve never been able to solve. Their first one. The one that left them orphans.
During a completely unrelated case they find an intriguing piece of information that could help them find their parent’s killers, but only if they survive long enough.