WARNING: The following contains spoilers for Archive 81, now streaming on Netflix.
Archive 81 has cult leaders sacrificing innocent people, a sketchy CEO and a literal demon god. But if that isn't enough to understand that Archive 81 has horrible people as characters, look to Dan Turner, who's nothing but a bad friend to Mark.
In Archive 81, Dan enlists the help of his best friend Mark when he is forced inside an isolated compound taking on the job of restoring damaged videotapes found in a mysterious fire. Without internet or cell phone service -- with the exception of a few spotty areas -- Mark is the only person Dan can trust to uncover the secrets of the tapes created by Melody in 1994.
Mark may be a jerk sometimes -- even his promotional voicemail comes off as conceited -- but he has all the right intentions when it comes to Dan. The young archivist spent time in a mental institution after experiencing a psychotic break, which stems from his traumatic childhood in which his entire family died in a house fire. What caused this break was a split from a romantic relationship, but it brings up his family's death, which is why Mark is always skeptical of something new and potentially endangering to Dan's mental health.
At one point, when Mark thinks Dan has hit his lowest -- he believes he's hallucinating conversations with Melody and being held captive by the secretive CEO Virgil Davenport -- he visits Dan at the compound, going out of his way to find the hidden place to make sure his best friend isn't experiencing another breakdown. But Dan turns him away, giving him no apparent reason as to why and only has an interest in speaking when Mark brings up that he found Thomas Bellows, one of Dan's many requests.
Even though Dan wants to finish the job to discover his father's connections to the Vos Society cult, Mark thinks it's in Dan's interest to cut ties with Virgil, who has no background or history. Dan takes this as an insult to his ability to work through his mental health, which he's obviously insecure about. Time after time, Dan asks Mark to research missing people for over 20 years, hackers who can break any code and lost footage from the 1920s. It's a miracle Mark is willing to find all the answers, but it's even more of a miracle that he never goes off on Dan for all the excessive favors.
Dan only ever seems to express his gratefulness to Mark twice in the show; first when Mark goes to talk to an older Melody, who turns out to be a fraud, and second when Mark agrees to perform the satanic spell to find Melody in the Otherworld. But the second time was only after Dan accuses Mark of doing all these ridiculous errands just to have a story for his podcast, which rightfully offends Mark. The two make up easily, and it's probable to assume that Mark forgave him so quickly to avoid another psychotic break caused by a meaningful relationship's end.
But Mark never complains. In fact, he goes out of his way to create diagrams and elaborate boards to help Dan unravel the mystery, which is far more than he was asked to do. It may seem as though Mark began to believe the illusion at some point, but more so it represents an act of friendship that Dan doesn't reimburse. Mark clearly has his own life with his podcast and friends, which Dan never does a double-take on when asking Mark for a favor or considering thanking him for his time well spent. Even when Mark risks his own life by diving into the personal lives of dangerous people, and knocking out Virgil to save Dan at gunpoint, Dan just sees this as a casual move of friendship that needs no mention.
That's not all to say Dan is a horrible person. He willingly performs a dangerous ritual opening a door to the demonic Otherworld to rescue Melody, and consistently wants to believe the good in his father. But Dan can't seem to extend his friendship far beyond one person at a time. Melody was his priority the second he assumed she was in danger, and Mark was left in the dust from there.
To see Dan mistreat Mark throughout the series, stream Archive 81 on Netflix.