The new owner of the much neglected fourteenthcentury castle in Morąg commenced a gradual restoration of the whole building. Repair and construction conducted in 2002 were preceded by a search for murals in the castle interiors. All the interiors were examined by means of uncovering methods applying the cross-strip system as well as a non-invasive method based on solvents. Both investigations and earlier quests led to the discovery of sixteenth- and seventeenth-century vaults richly decorated with ornamental polychrome and figurai motifs in the tondos. The researchers also uncovered fragments of murals in ground-floor interiors underneath numerous layers of plaster and lime whitening. Finally, the author describes a series of examinations of the plaster and brick walls.