Awdur(on)/Author(s) : Meilyr Siôn
Darlunydd(ion)/Illustrator(s) : Matt Abbott
Mae siop Anti Carys sydd yng nghanol y dref, ac sy'n cynnwys modrwy go arbennig - Carreg y Ffin - yn darged i ladron sy'n gweithredu yn y dirgel. Ond pwy yw'r lladron hyn sy'n ceisio dwyn y fodrwy? Ceisia Meena a'i chefnder, Wil, ddatrys y dirgelwch.
Aunt Carys's shop, which is in the centre of the town, and which contains a very special ring - Carreg y Ffin - is a target for thieves who operate in secret. But who are these thieves that are trying to steal the ring? Meena and her cousin, Wil, try to solve the mystery.