[5] In the season 2 episode "Vendetta", it is revealed that Artie was trading artifacts in exchange for the release of family members who are political prisoners in the Gulag.

In the season 1 episode "Claudia", we learn that 12 years earlier, Artie posed as a professor to get close to graduate student Joshua Donovan, to help him.

Starting with the season 1 episode "Implosion", MacPherson returns as Artie’s nemesis – collecting and auctioning off artifacts to release them back into the world.

As revealed in the season 3 finale, "Stand", when preparing for Sykes' attack on the Warehouse, Artie takes a watch that MacPherson gave to him, hoping that he would never have to use it.

Realizing that the watch can lead them to a fail-safe that can reset 24 hours, Artie, Claudia, Pete, and Myka set out to find the artifact.

Artie is approached by Brother Adrian of the Templars, asking his assistance in finding the person who used the astrolabe, insisting that it must be used again to restore the timeline and prevent evil creation.

As Artie's behavior becomes more and more erratic, he is approached by Mrs. Frederic, Leena, and H. G. Wells and, in the episode "Second Chance", he reveals to them the story of the astrolabe and Brother Adrian.

In the episode "We All Fall Down", it is revealed that Artie's evil plan is to release a deadly disease, the English Sweating sickness, into the world.

He has suffered no physical injury from the dagger, but he has retreated into his mind, not wanting to come out of his coma and face the memory and act of killing Leena.

He begins to take over Leena's chores and responsibilities back at the warehouse, initially refusing overtures from Myka and Steve to help.

The Regents take action by assigning Dr. Abigail Cho to Warehouse 13, who is introduced to Artie by Mrs. Frederic in "The Sky's the Limit" as the new owner of Leena's B&B.

He obsesses about minutiae to the point of neurosis and has been known in the past to leap to conclusions based on precious little evidence beyond "gut" instinct.

Artie frequently tries to protect the people with whom he's forged relationships, either by making them promises to do so (whether or not he can keep them) or by swearing to potential attackers that he won't allow harm to come to those about whom he cares.

In one instance, he finds an important document in his office card catalogue, exclaiming "Google, shmoogle, I’ll stick with paper.

His thirty-plus years as a Warehouse Agent have taught him the unpredictable nature of artifacts, causing him to proceed with caution in any situation.

He is also able to improvise gadgets out of household items; he made an electromagnet out of iron in "Merge With Caution" and used a broken windshield and his Tesla to overload Pete's ocular input in "Around the Bend".

As revealed in the season 2 episode "Vendetta", Aleksandr was Artie's Soviet contact during the time that he was trading artifacts in exchange for the release of family members from the Gulag.

We learn in the season 1 episode "Implosion" that Mrs. Frederic is responsible for Artie's recruitment to the Warehouse, starting a relationship that has endured at least 30 years.

After being institutionalized for years with half his brain downloaded into a computer, his mind is made whole again when Artie reverses the process using the same artifact that causes the initial separation.

After being freed from the astrolabe's control, Artie feels great grief and guilt over Leena's death, knowing that it was his hand that killed her.

In the episode "The Sky's the Limit", he seeks the consul of psychologist Abigail Cho, telling her, "I killed someone I love, and I don't know what to do."

We also witness Artie's emotion in "The New Guy" upon seeing that Myka has returned to the Warehouse, simply uttering "Good" with a satisfying smile on his face.

In the season 2 episode "Age Before Beauty", we see Artie's uneasiness with the role of a father figure when his attempt to advise the teenage Claudia on a matter of romance ends in an awkward exchange.

In "Reset", as Artie recovers from a gunshot wound, Claudia breaks into tears at the thought of something grave befalling him, to which he assures her, "Kiddo, hey, I plan on making your life hell for a very long time."

In season 3 episode "Trials", Artie secretly follows Claudia on her first lead assignment because, like a proud parent, he wants to be there to see her succeed.

His feelings about Helena begin to soften somewhat in the episode "Where and When" after she struggles to repair her time machine to save the lives of Pete and Myka.

Artie's distrust of Helena is vindicated when she's revealed to be a villain, as she attempts to initiate a worldwide disaster in the season 2 finale, "Reset".

In the season 2 episode "For the Team", Artie is discovered to be re-growing his appendix to invite a visit from the official Warehouse physician, Dr. Vanessa Calder.

Heartbroken, Artie confides to Claudia, "Given my line of work and my advanced years, I have pretty much made peace with the fact that I would not find romantic companionship.

Artie feels that the time is right to take things 'to the next level'; however, their date is interrupted by Alice's escape from Lewis Carroll's mirror.