Making of a murderer
or how a chatbot receives a personality

13. August, 2021 | Hoa Le van Lessen

Crimescene: an office loft in Berlin-Kreuzberg. Large window front, clinker walls, lots of glass

The perpetrators and victims: The entire team.

BREAKING NEWS: “A clear case of Stockholm syndrome: after the staff fell victim to a workshop lasting several hours on a Friday afternoon, several people still wanted to try their hand at flipchart conversations instead of diving into the weekend.”

Full story

Conversational User Interfaces (CUI) are becoming more and more commonplace. Over 50 million households already own a smart speaker, and most of the world’s three billion smartphones have access to Siri (Apple) or Google Assistant. When we text or talk to them, we communicate with a character. This character doesn’t have to have names and gender like Siri, see Google Assistant, but there has to be a recognizable “sound”, a Tone of Voice.  

The challenge: What is the appropriate Tone of Voice? How do you realize an ideal “Voice” and “Brand” match? We tried out one method in our chatbot prototyping workshop. The goal of the workshop was that at the end a (human) chatbot could be “tested” by a  group of people.

The required equipment and setting.


⏱ 30 min

There are two ways to getting started. Either you take an existing business and try to develop a chatbot persona for it, or you invent a new business. We tried both: Group 1 worked with an existing business, they knew from a previous project or collaboration. Group 2 thought up a business. Let’s have a closer look at that one.

Fake it. The group with the new business idea was more creative, had more fun, and focused more on structure and methods rather than details and feasibility.

The group kicked it off starting from scratch. A blank flip chart and 10 minutes to generate a business idea. First sprung ideas from the mail order business: flower mail order, pet food mail order, pet toy mail order. Flower vases with individual flower motifs. Then the team shifted towards service provision: dog-sitter agency, wailer agency, ghostwriter agency. Great idea came about, although the team was not really satisfied, until the last 3 minutes approached.

The team looked around, every corner of the room, every person in the room, every little detail was investigated. Finally! Looking at their senior coder. Dressed all black, with his dark sense of humor, he was known for. Suddenly the solution was right in front of them. “Let’s take a service, dark as can be, nobody of our team has thought about. Bingo! Let’s build a service for our contract killer agency. Real fixers. The mood in front of the flipchart changed from perplexity to tension. Who could be the killer?“

⏱ 5 min / table field; expandable

The Business

Brand Name: Death2go

Tasks and Services: Death Threats, Artistic Murder, Friends & Family, War of the Roses, Ex-Special, Crime Scene Cleaning, Revenge, 3 for 2, Animals, Crime Scene Decoration and Manipulation.

Brand Values: individual, friendly, precise, serious, goal-oriented, discreet

The Chatbot

Tone of Voice: understanding, familial, sermonizing, traditional, metaphorical, Italian, life-experienced

Persona: modeled on Marlon Brando’s character “Don Corleone” from the movie “The Godfather”; male, about 50 years old, with a sonorous voice, light Italian accent with a slightly purring speech melody

Name: “Don Giovanni” like the favorite trattoria around the corner.

Download Chatbot Prototyping Worksheet


⏱ 30 min

To generate a real dialogue as a mock-up conversation, you need a sparring partner – the so called ‘user persona’. The user needs the service to solve a need/issue. The user task is the challenge to be solved. The team decided on the overall user story to be tested. In our journey the task was crystal clear, why the user needed us. Somebody had to die.  

So in which context? What was the user story to demonstrate our service?

– My landlord raised the rent – I want to intimidate him (2 votes). 

– My great aunt doesn’t want to die – I have to inherit now (3 votes) 

– My ex-wife sued me for high alimony payments – she has to disappear (2 votes) 

– My boss is an asshole- my honor is worth his blood (4 votes) 

After a timeboxed session of 10 minutes, the journey was all set.

The Story

Tim, 42 (verheiratet, 2 Kinder), IT-Hausmeister in einem Immobilienkonzern. Tim sollte alle Feuerlöscher der Etage Tim, 42 (married, 2 children), IT admin for a real estate company. The new fire safety guideline requires to hang all fire extinguishers on the floor 10 centimeters. During a staff meeting Tim attempts to mount another fire extinguisher on the wall, when suddenly Tim drops one of the fire extinguishers. Tim’s boss who was bragging about his new Maserati in front of the team, turns around and starts humiliating Tim in front of the whole team. He threatens to fire him, pulling fire extinguishers off the wall. When Tim and Paula’s eyes meet… Paula the attractive accountant..  

Download Chatbot Prototyping Worksheet


⏱ 30 min

What information does the bot need to fulfill the user’s goal? Our gentleman-killer bot needs the same information which a reporter will need later: Who? When? Where? And How?  

How should the chatbot conduct the conversation to get this information? In what order? Which language?

This step provides us with space to be creative and try out different versions of the chatbot’s persona: understanding, familiar, soap, traditional, metaphorical, Italian, life-experienced.

Our chatbot prefers to speak in metaphors. Thus it’s essential to compile a list of metaphors in advance: 

Murder/Dying: Going on vacation, going on a trip, taking a nap, lying down, resting, wearing a suit, [suffering] a misfortune, being in a better place, meeting again later, pushing the daisies, 

Types of death: looking a little deranged, wet or dry, being in company, I heard he couldn’t brake, an accident, sudden, unexpected, etc. 

Financial: my daughter wants to have a wedding, cut the cake first, then buy the dress, go on a cruise, accept an inheritance, invest

An example flow 

The example flow gives the group an idea of how to make the Tone of Voice audible in an interaction with the user.


“Good evening, thank you for calling. Would you like to get some information or speak with Don Giovanni right away?”    

“Good evening, we have been expecting your call. Would you like me to connect you, or would you like Don Giovanni to call you back?”

“You have already been expected by Don Giovanni. One moment, you will be connected.”

Main Flow 

“Don’t worry about it. Nobody is harmed by a little nap. Who would like to take the nap?” (Who?) 

“My boss.” 

“What’s his name?” 

“Ansgar Maier.” 

“Where does Mr. Maier like to lie down?” (Where?) 

“In the office” 

“Si, certo. I understand. Many people get so terribly tired in the office. Does Mr. Maier prefer to rest alone, or among people?” 

“It would be nice if the colleagues could be there” (How?) 

“I understand, he can’t get away from his desk. Bene. What time could I reach him, do you think?” 

“Right after lunch would be good.” (When?) 

“Si maestro, I understand. After lunch is a particularly good time to go to sleep. I have a cousin who sweats so much in his sleep that everything gets wet. Is it the same with Mr. Maier?” 

“Absolutely. He’s supposed to sweat a lot, the doctors say.” 

“I see. Grazie. Have you ever had strawberry stains? They’re so hard to get out… But Mr. Maier is getting a new suit. Do you have any ideas for a little present for il Signor?” 

“A fire extinguisher would be best.” 



⏱ 2 x 20 min

One person develops the chatbot dialogue pieces. This person takes on the role of the chatbot. Another person from the other group is selected to “test” the chatbot as the user. The team is presented with the user persona and user story. The conversatiton was created by the group members, who developed the chatbot. The “chatbot” itself tried to respond with as many unchanged sentences from the happyflow as possible. Then it proceeds to the feedback loop. The same is repeated with the other group. 

The Don Giovanni persona was already quite entertaining in its overall presentation. Even if he wasn’t full able to respond instantly (on the flipchart) he passed the first user test with flying colors. 

Humor is an essential element, to mask shortcomings, if infused in the right moment. 


Depending on the objective of the particular chatbot and use case it might be useful to include iterations, deviating from the initial script to test errors and edge cases. 

Our workshop took place on a Friday afternoon and our chatbot and user said goodbye to the weekend after the first test. 

Don Giovanni doesn’t have his own phone number yet and the fire extinguishers have not been touched in the office since. 

About the boss… he doesn’t own a sportscar and is well.