Chase is described as "about Spencer's height and well-built." He has sharp green eyes and "a sensual, pink full-lipped mouth." He also has white scars across his cheeks, has slashes on his hands, and has one of his ears shriveled and "barely there."
In Crushed, Spencer was desperate for proof that Real Ali was still alive after the explosion in the Poconos, so she Googled information about "Alison DiLaurentis conpiracy theories" and contacted an investigative blogger named Chase who seemed to know a lot of information about Alison. Chase agreed to chat with Spencer online, even though she wouldn't tell him what her name was or how she was connected to Alison.
Chase suggested that he call Spencer "Britney Spears" as a placeholder name until she was ready to reveal who she was. He also started "cyber-flirting" with Spencer, calling her smart and saying how their combined IQ would be "out if control." Spencer sympathized with Chase because he was stalked by his roommate at his boarding school and was almost killed by him. Chase said that that is why he is interested in the case—not only is it a weird story, but he has also been in a similar situation with a stalker.
Chase said that he thinks that Alison got out of the house in the Poconos before it exploded and that she had at least one accomplice who had helped her kill Jenna Cavanaugh and Ian Thomas and helped her get a private nurse to take care of any injuries she may have gotten. With some research, Chase deduced that Alison's nurse must not have gone through an employer or medical supplier, so the supplies for Alison must have come from regular drugstores. A friend of Chase's who works at CVS told him that one drugstore has regular orders of large amounts of bandages and wound-cleaning supplies and also got a surveillance video of someone picking it all up. The person is believed to be Barbara Rogers, a woman in her mid-fifties, but not much else was figured out about her. Chase also figured that, since Ali wouldn't be using a prescription for her drugs, she would have to be getting them illegally. He found out that there was a pharma theft not long ago at Bill Beach, the Rosewood burn clinic where Hanna was volunteering again to find out information about Graham.
When Spencer chatted with Chase a second time, he told her that he talked with Billy Ford about any interaction he may have had with Alison before he was arrested and found out that Billy was visited by a person from the Geek Squad who offered to scan his computer for free. This person, who was a guy, may have been Ali's helper and planted those incriminating photos and messages onto his computer to frame him as "A." Also, an anonymous person sent Chase photos of Alison and Courtney when they were younger. Spencer said that she and Chase should meet in person at Mütter Museum so he could show her the photos.
Spencer, wearing a blonde wig and sunglasses to protect her identity, met a boy there who claimed to be Chase and who showed her the pictures of the twins. One picture was of two blonde girls, about five years old. The other was of Ali, Jenna, and who they thought was Naomi Zeigler in a photo that "A" had previously sent Emily, saying "One of these things doesn't belong. Figure it out quickly . . . or else."
Chase and Spencer agreed to meet again at an apartment complex that Barbara Rogers was traced to, where Spencer finally revealed her identity as one of the girls Alison tried to kill to Chase, who was taken completely by surprise. Spencer also, on impulse, asks Chase to the prom, and he accepts. Then, when they knocked on Barbara's door, they got no response. Chase, who was leaning against another door, accidentally slammed his hand hard against it, and an attic door on the ceiling opened and all of its heavy, dangerous contents spilled out, almost landing on Spencer's head. The pair leave right afterward, shocked.
On prom night, Chase picks Spencer up in a limo. During the ride, he tells her about a surveillance video he found from a nearby building with a girl that looks like Alison in it. When a story about Tabitha Clark came on the radio, Chase asked about how Spencer was in Jamaica the same time that Tabitha was killed. Spencer became freaked out, saying that she never told him that. She then suspected that he was Ali's helper all along, feeding her Ali's secrets, planting information on others' laptops to frame them, and setting up the attic to fall on Spencer. She then distracted Chase temporarily and ran out of the limo, into an alleyway. She tried to call a cab, but "A" sent her a message saying, "You can run, but you can't hide, Spence!" Right after, her phone mysteriously shut down completely. Later, Spencer finally got a cab to the prom. She was ready to tell Emily about Chase being Ali's helper when Emily informed Spencer about Iris recognizing Noel Kahn as Real Ali's secret boyfriend/helper, proving Spencer wrong about Chase being "A." The day after prom, a boy showed up at Spencer's door, claiming to be Chase. When Spencer told him that she had met Chase, he told her the truth, which is that he was the actual Chase who was chatting Spencer online, but panicked when he saw how pretty Spencer was in person, so he sent his brother, Curtis, who was in the car with him, in his place, not wanting Spencer to be repulsed by his scars and slashes that he got from his stalker roommate. Chase also mentioned that he had had a crush on Spencer since he saw her in a magazine for the Alison DiLaurentis story and that he and Curtis got into a fight on prom night because Chase thought that Curtis should come clean, though he didn't want to. Chase showed a flattered Spencer the surveillance footage with the girl who looked like Alison, and Spencer forgave him for lying to her.
In Deadly Chase meets up with Spencer at the hospital. He claims he might of found Ali's secret hideout. Him and Spencer head there only to be confronted by a man who claims that the lot was vacant and no one stayed there. They leave thinking it may be a trap.