In his childhood, Ian lost both of his parents in a murder-suicide perpetrated by his father. As an adult, he became a plumber alongside his uncle. He also led a secret life as a drug dealer, and eventually befriended one of his clients Doug Hoffer. He also became acquainted with Doug's wife Kate, smoking weed with her once. However, the friendship was short-lived when Kate quit her ways so she could become a better mother to her daughter Gabby. Eventually, Kate divorced Doug and left with Gabby, while Ian met Sue Walsh, a cousin of Kate's, with whom he started a romantic relationship. A couple of days prior to "Gabby", Sue, wanting to exact revenge on Kate, tried to recruit Ian and Doug to help her in abducting and presumably killing Gabby, but when Doug refused and was subsequently killed by Sue, Ian helped her to dispose of his body. He initially tried burning it, but wound up burning his face severely in the process. Then, Ian dumped Doug's body into a nearby river.
In "Gabby", the BAU, who are called in to investigate Gabby's disappearance, initially suspect Doug of being behind the crime. Their investigation comes to center on a dark van that picked up Doug days prior to the abduction, and Garcia eventually finds a van under the ownership of Ian's plumbing company. This leads to Ian's arrest; he tries covering for himself and Sue by saying that he received the burns on his face during a cooking accident, but the BAU easily see through the lie. When Hotch tries asking for Gabby's location, Ian denies any involvement and then asks for a lawyer. However, an unfazed Hotch tells him that he already has all of the answers he needs, as there is a search being conducted at his home and the area around it. While the search doesn't turn up Gabby, it instead turns up Doug's body. When the BAU deduce Sue's involvement and that she killed Doug, Hotch confronts Ian and gives him a deal to a reduced sentence, to which Ian decides to tell him the circumstances of Doug's murder. Ian is last seen being taken into police custody.