In a story that feels like something out of Black Mirror, a man has created a speaking and artificially intelligent virtual robot to act and talk like his deceased father.

Before James Vlahos lost his father John to lung cancer in February 2017, he recorded dozens of hours of conversations. These included stories and jokes told by his father. Once transcribed, the text totalled 91,000 words across 203 pages.

Called Dadbot, the artificial intelligence (AI) system operates through Facebook Messenger, the chat platform used by bots developed by brands to interact with customers. The bot can hold written conversations based on the text collected by Vlahos, and occasionally play a recording of his father telling a joke or singing a song.

"I think I have found a better way to keep my father alive," Vlahos, a journalist, wrote in Wired magazine.

At first Vlahos intended the 200 pages of transcripts to go no further than a bookshelf at home. But he then discovered PullString, an artificial intelligence company made up of former Pixar staff who want to create technology enabling conversations between real, living humans and fictional characters, or people who have died.

Vlahos was initially conflicted over developing the Dadbot, over fears it would "simply fail in a way that cheapens our relationship and my memories. The bot may be just good enough to remind my family of the man it emulates – but so far off from the real John Vlahos that it gives them the creeps".

'Building a robust, knowledgeable Dadbot'

The bot's conversations structure was based around a simple architecture, beginning with a short exchange around a greeting, then moving on to discuss one of various chapters of Vlahos' father's life. As an economics graduate from Berkeley, sports editor of The Daily Californian, a managing partner of a major law firm, an announcer in the press box of Berkeley's Memorial Stadium, an actor and a volunteer San Francisco tour guide, there is plenty of subject matter to discuss.

Vlahos spent months writing scripts for the chatbot to use in every scenario, using phrases gathered from the transcriptions of his father's conversations. The Dadbot has been programmed to sometimes take the lead in conversations, and adjust its answers based on how the other person says they are feeling.

PullStrings then added a feature where audio replies can be added into conversations, giving Vlahos the chance to take clips of his dad's stories and add them to the bot's growing roster of answers.

When tested by his mother, the Dadbot showed how it understands who it is talking to, and will then bring up memories the two of them have shared, such as holidays together from decades ago.

After his father's passing, Vlahos surprised himself with a growing desire to keep working on the chatbot, perfecting it and making it seem more human. Vlahos writes: "As an AI creator, I know my skills are puny. But I have come far enough, and spoken to enough bot builders, to glimpse a plausible form of perfection. The bot of the future, whose component technologies are all under development today, will be able to know the details of a person's life far more robustly than my current creation does...[it] will even be emotionally perceptive."

Speaking to the As It Happens show on CBC Radio, Vlahos said of using the Dadbot: "It either brings a smile to my face and a warm feeling sometimes, and at other times it brings a tear to my eye... It can make him feel closer sometimes, or I can be painfully aware that I'm talking to a computer program that I created that very clearly is not him."