In the story, a British antiquary named Somerton follows a coded message, hidden in a stained glass window, which leads him to a location in Germany where a large amount of gold is hidden. When he takes the treasure, Somerton finds that a ghost will not allow him to have any rest until the gold is put back in its original hiding place.
Readers should be aware that "The Treasure of Abbot Thomas" contains a large amount of Latin text, not all of which is translated immediately.
The story has been adapted to other media, most notably as the fourth TV movie in the BBC series A Ghost Story for Christmas.
In 1854, the British antiquary Justin Somerton reads a book written in Latin about the Abbey of Steinfeld in Germany. He reads that Abbot Thomas von Eschenhausen, who died in 1529, had the Abbot's house rebuilt, had a well dug in the house's grounds and had a stained glass window installed in the Abbey Church. He also reads that Abbot Thomas was rumored to have hidden a large amount of gold somewhere in the monastery. Whenever anybody asked him where the treasure was hidden, Abbot Thomas replied, "Job, John and Zecheriah will tell either you or your successors."
Justin Somerton believes that the stained glass window from the Abbey Church holds the clue to locating Abbot Thomas' hidden treasure. He knows that a lot of German stained glass was taken to England after the German monasteries were dissolved. He remembers having seen an obviously 17th century German stained glass window in the private chapel of a nobleman referred to only as Lord D--. The window depicted the Biblical figures Job, John and Zecheriah. each of them was holding a book or a scroll on which something in Latin was written. In the notes which he took when he visited the chapel, Somerton translated the three Latin inscriptions as, "There is a place for the gold where it is hidden", "They have on their vestures a writing which no man knoweth" and "Upon one stone are seven eyes."
Somerton pays another visit to Lord D--'s private chapel. He examines the stained glass window very carefully but cannot see any writing at all on the three figures' clothes. He notices, however, that all three men have ugly black borders on their robes. Lord D-- enters and sees that Somerton's hands are black from touching the dirty stained glass window. He orders one of his servants to clean it. When the servant cleans the window, some gold lettering is exposed beneath the black border on one of the figures' robes. Somerton finds that the rest of the black border can be scraped away easily. He obtains Lord D--'s permission to remove the black borders and reveal the hidden inscriptions. He notes down the seemingly meaningless jumble of letters that he sees. He realizes that the message is in code.
At home, Somerton makes several unsuccessful attempts to crack the code. Looking at the other notes he wrote about the stained glass window, he is reminded that Job is shown holding up one finger, John two fingers and Zecheriah three fingers. He realizes this means that, after the first letter in the message, he should skip one letter, after that he should skip two and after that he should skip three. He decodes the message and translates it from Latin as, "Ten thousand pieces of gold are laid up in the well of the court of the Abbot's house of Steinfeld by me Thomas who have set a guardian over them". At the end of the message, written in Old French, are the words, "Whoever touches them, beware."
Soon afterwards, Somerton and his servant Brown go to Germany and stay at the local inn in Steinfeld. Somerton finds the former site of the Abbot's house, which is now surrounded by fields and orchards with no inhabited buildings nearby. He finds the well. He notices that it is decorated with scenes from Bible stories but has none of the cryptic inscriptions typical of abbot Thomas on it. Somerton notices a staircase, which does not look difficult to descend, inside the well. At night, having told the inn's landlord that he was going to sketch the abbey by moonlight, Somerton returns to the well with Brown. They carry a carpet bag containing rope, lanterns, candles and tools. Having made sure that nobody is watching, they go into the well and go down its staircase.
Somerton looks for the stone with seven eyes on it. He notices that one slab seems to be made of cement rather than stone. He strikes at it. The cement comes off and a stone with seven eyes carved on it, arranged in the form of a cross, is revealed. Somerton finds that he can remove the slab easily and that there is a cavity behind it. Reaching into the cavity, Somerton removes a large leather bag. He then feels arms around his neck and a cold face pressed against his. He smells mold and feels arms, legs or tentacles clinging to his body. Somerton later says that he believes his attacker to be the ghost of Abbot Thomas himself. He screams and falls over. Brown is able to get Somerton out of the well and back to the inn.
For the rest of the night, Somerton is unable to sleep. Brown sits up with him. The following morning, Somerton finds that he is unable to get out of bed. He asks Brown to write to his friend Gregory the clergyman to tell him that he is ill. To get rid of the smell of mold, Brown burns all the clothes that Somerton wore when he was in the well. At night, Somerton finds that the smell of mold is still there, although it appears to be coming from outside his bedroom door. He also hears faint sounds outside his door and has the feeling that someone or something is watching his room. In the morning, the noises stop and the smell goes away. Somerton realizes that the ghost which is watching his room is a "creature of darkness" that cannot stand the daylight.
In response to Brown's letter, Gregory comes to Steinfeld. Somerton begins to recover in the presence of his old friend. He makes Gregory promise to do something for him early the next morning but refuses to say what that thing is. Somerton says that the task will not be dangerous in the daylight. Gregory agrees. That night, Gregory hears "fumbling about the lower part of his locked door." In the morning, Gregory goes to the well with Brown. Gregory puts back the treasure. He and Brown replace the slab and smear it with mud so that it looks like the others.
It is only when Somerton, Brown and Gregory have left Steinfeld and begun their journey back to England that Somerton tells Gregory the whole story. Gregory has no trouble believing Somerton's story because he is certain that a ghost was watching his bedroom the night before also. He also says there is a marble sculpture on the well which Somerton failed to notice. The sculpture depicts a toad-like beast. Near to it is a Latin inscription which can be translated as, "Keep that which is committed to you."
"The Treasure of Abbot Thomas" was somewhat loosely adapted as the fourth TV movie in the BBC series A Ghost Story for Christmas. The film was first shown on British television on December 23, 1974. It stars Michael Bryant as Justin Somerton and Paul Lavers as Lord Dattering (who, in some respects, resembles the character of Gregory from the original short story). The character of Brown is omitted. The entire film takes place in England. The hidden treasure of Abbot Thomas is located near to Somerton's house. In the adaptation, Justin Somerton is an ordained Anglican priest and a lecturer at Cambridge University. Lord Dattering is one of his students. It is established early in the film that Somerton is a skeptic. He interrupts a faked séance and exposes as charlatans two mediums who had told Lord Dattering's mother that they could help her contact her late husband. Abbot Thomas is said to have only escaped execution for witchcraft by having been carried off by the Devil first and to have believed himself to be an alchemist. For that reason, Somerton believes that the treasure may really be base metal which Abbot Thomas incorrectly believed he had turned into gold. When he tells Lord Dattering to put the treasure back, Somerton says that his suspicions were confirmed and that all he found was a purse full of worthless metal. When Lord Dattering looks in the purse, however, he sees that it is full of gold coins. Whether or not the treasure was returned is not revealed. In the last scene of the film, the ghost of Abbot Thomas returns to take its final revenge on Somerton, suggesting that the treasure remained unreturned.
The 1989 Italian horror film The Church (La chiese) is a very loose adaptation of "The Treasure of Abbot Thomas".
Other short stories in which codes are cracked:
- The BBC series A Ghost Story for Christmas is made up of fifteen TV movies that were first shown on British television between 1971 and 2021. Of the other fourteen films in the series, three are original stories, the rest are adaptations of the short stories "The Stalls of Barchester Cathedral", "A Warning to the Curious", "Lost Hearts", "The Ash-tree", "A View from a Hill", "Number 13", "Oh, Whistle, and I'll Come to You, My Lad", "The Tractate Middoth", ""Martin's Close" and "The Mezzotint" by M.R. James and the short story "The Signalman" by Charles Dickens.