The Watcher house. Picture: Realtor.com

Lee Levitt, a lawyer for Derek and Maria Broaddus, wrote in a legal brief that the letter arrived in late February, a few weeks after a tenant rented and moved into the Westfield home. It’s the fourth letter the couple has received from “The Watcher,” who claims he is the rightful owner of the home the Broadduses bought for nearly $1.8 million ($US1.4 million) in 2014.

Levitt says the letter contained specific threats and was “more derogatory and sinister than any of the previous letters.” Westfield police declined to comment on the latest letter, citing an ongoing investigation.

In one of the earlier correspondences, the stalker asked whether the new family brought him the “young blood” that he requested. The Broadduses, who have young children, refused to move into the home and have been unsuccessful in their attempts to sell the property.

They sued the prior owners of the house in June 2015, claiming that they also received a letter from “The Watcher” but never disclosed it. That family has since countersued, stating that the letter they received was not threatening and alleging that they were defamed.

The Broadduses have said they can’t live in the house because of the letters, which they say came from someone with a “mentally disturbed fixation” on the home.

They are also suing Westfield because the town’s planning board rejected their plan to raze the house and subdivide the land so they could build two houses.

THE WATCHER’S TERRIFYING NOTES

• “(The house) has been the subject of my family for decades”

• “I have be (sic) put in charge of watching and waiting for its second coming”

• “My grandfather watched the house in the 1920s and my father watched in the 1960s. It is now my time”

• “Why are you here? I will find out”

• “Now that they have to flaunt it, they pay the price”

• Tsk, tsk, tsk ... bad move. You don’t want to make 657 Boulevard unhappy”

• “Do you need to fill the house with the young blood I requested?”

• “Once I know their names I will call to them and draw them too (sic) me”

• “I asked the Woods to bring me young blood”

• “Have they found what is in the walls yet? In time they will”

• “I am pleased to know your names now and the name of the young blood you have brought to me”

• “Have you found all the secrets it holds?”

• “Will the young bloods play in the basement”

• “Who has the bedrooms facing the street? I’ll know as soon as you move in”

• “It will help me to know who is in which bedroom then I can plan better”

• “All of the windows and doors in 657 Boulevard allow me to watch you and track you as you move through the house”

• “Who am I? I am the Watcher and have been in control of 657 Boulevard for the better part of two decades now. The Woods family turned it over to you it was their time to move on and kindly sold it when I asked them to”

• “You have changed it and made it so fancy”

• “It cries for the past and what used to be in the time when I roamed its halls”

• “When I ran from room to room imagining life with the rich occupants there”

• “And now I watch and wait for the day when they (sic) young blood will be mine again”

• “657 Boulevard is turning on me it is coming after me”

• “I am in charge of 657 Boulevard”

• “Let the young blood play again like I once did”

• “Stop changing it and let it alone”