Dingus' name and silhouetted image first appears on Webby's conspiracy board, near pieces of paper reading "Scrooge's Worst Nightmare" and "Friend or F.O.W.L."; it is also visible in subsequent episodes.
Dingus is among the McDuck relatives whose portraits hang in Castle McDuck; he is specifically noted as Fergus' father. Scrooge and Fergus later discover that Dingus' relationship with Fergus was not unlike their own. As such, Dingus hid the Treasure of the Knights Templar, leaving a note for Fergus challenging him to find it.