After a night out in the town on Wednesday, August 17, the victim returned to his home in Marriott Street with two people he had met earlier in the evening. While at home, the victim was allegedly assaulted by one of them and knocked unconscious.
Electrical goods and other items were also stolen from the property.
Officers would like to speak to the man and woman pictured, who they think may have information about the incident.
Anyone who recognises them is being asked to contact Northamptonshire Police on 101.
The alleged incident happened between 10pm on Wednesday, August 17 and 5am on Thursday, August 18.