Harry is one of the founding members of Ghostfacers.
Along with Ed Zeddmore, he was a 'professional' paranormal investigator. He also co-ran the website HellHoundsLair.com.
Ed and Harry investigate a supposedly haunted house, where they run into Sam and Dean, whom they presumed to be glory hounds looking for cheap thrills. The HellHounds believed themselves to be close to paranormal activity with their EMF meter spiking high, unaware that the overhead power line was interfering with the reading. Ultimately, both parties found nothing and left.
Ed and Harry later return to the house after learning of a teenage girl being strangled by the ghost of Mordechai Murdoch. However, the house was being guarded by state troopers to keep anyone else from going in, so Dean alerts them to the presence of the amateur ghost hunters, who begin chasing them. After Ed and Harry managed to elude the cops and return to the house, they find the Winchesters crashing out the front door, before spotting Mordechai appear in the entrance. Terrified, the boys attempt to run, only to be caught and arrested. They try pointing out Mordechai, but the ghost had vanished.
After being released from jail, the duo posted their footage of Mordechai on their website, increasing their website's popularity. Unbeknownst to them, they had already had a hand in creating a Tulpa, as a result of the Tibetan spirit sigil being posted on their website, the collective thoughts of all their viewers inadvertently bringing Mordechai to life and all the new legends posted constantly change his nature.
Harry was too sacred to return to the house, whereas Ed carelessly thought otherwise, urging his friend to think like Buffy the Vampire Slayer. They then get a rude knocking from the Winchesters, who demand that they shut down their website, stating that it would attract more people to the hell house for Mordechai to slaughter. Harry was quick to agree with them but proved fickle and sided with Ed, who irrationally claimed they had an obligation to their fans and to the truth. And so the Winchesters gave them a new legend to post in exchange for shutting down the website, claiming that Mordechai committed suicide via pistol and his ghost was afraid of iron rounds. The HellHounds' ego got the better of them and they posted it.
When both parties returned to the haunted house, the HellHounds confess too late that their server crashed before the new legend could take effect. With Mordechai unstoppable, both parties fled the house, with Dean burning it down to the ground to destroy the Tulpa.
It was shown that Harry and Ed's adopted sister Maggie shared a mutual attraction, and end up holding hands and making out. When they met up again with Sam and Dean by accident it was when they and their team of "Ghosfacers" entered Morton House on a leap day with camera equipment to catch paranormal activity on film.
He and Ed are the only remaining Ghostfacers. Harry became engaged to a nice woman and was prepared to leave the Ghostfacers to live a normal life as an accountant under his future father-in-law until Ed claimed they needed to track down a ghost named Thinman, causing Harry to abandon his fiancee and rejoin Ed. They encounter the Winchesters when the Thinman claims a teenage girl's life. Despite the Winchesters threatening them to back off, they don't do so. The Ghostfacers and hunters later cross paths when Thinman murders a diner manager from the very diner they re-encountered the Winchesters. Later on, Ed attempted to convince Harry to leave Thinman to the professionals like the Winchesters, but Harry believed himself close to catching the ghost. Ed dropped Harry off in "the woods", which was actually some trees next to a grocery store. Harry soon ran into Thinman, and narrowly escaped with a cut across the stomach and kicking his attacker in the crotch before running into the Winchesters and Ed, who patch him up. Back at the motel, Ed confessed to Harry that he was the one who made-up Thinman. This greatly made Harry upset, blaming him for selfishly destroying his chances of a normal life and for living a lie, straining their relationship. While the Winchesters were chasing down Roger, the Thinman impostor, when Ed tells Harry his intention to follow the hunters to set things right, the latter decides to accompany him. The Ghostfacers arrive at the warehouse where Roger was supposed to be and split up, at which "Thinman" gives Harry a kick to the crotch as payback, but Ed draws a gun on him, only to be knocked out by Deputy Tom Norwood; the two men committed the murders as Thinman to get revenge against people who they believed wronged them. The criminal duo tell the Ghostfacers their plan to have Thinman murder them on camera to cover up the fact that Ed invented the legend. When they come back into the room with the Ghostfacers at gun and knife-point, the Winchesters jump them. Dean takes Roger out, while Harry shoots the deputy before he can take out Ed. Despite the relief, Harry was unable to overcome the guilt over having killed someone and refutes Ed's justifications for his lies by labeling him as selfish and leaves the Ghostfacers permanently. He then asks the Winchesters for a ride.
- His name is most likely a reference to Ghostbusters, with his last name being a modified spelling of last name of the character Egon Spengler and his first name coming from the actor who played the role, Harold Ramis.
- Harry and his friend Ed Zeddmore are both Buffy the Vampire Slayer fans.
- He and Ed Zeddmore are the longest living characters since Sam and Dean have already died multiple times.