Lucy has fair skin and light brown short hair with longer sides framing her rounded face and bangs covering her forehead. Her eyes are an oval shape and colored a deep crimson.
She usually wears a green blouse that resembles a military jacket with golden buttons. It has belts and buckles as accessories on the hem of the sleeves and on her hips, on which she puts her Scotland Yard badge. She also wears knee-length white trousers and, beneath them, grey stockings which cover her calves. Her shoes are rounded white and brown pumps with white shoelaces, and her hat a salmon-colored newsboy beret cap, which sometimes moves slightly when she jumps in surprise.
Lucy acts highly optimistic and confident, never shying away from her mistakes and troubles, always willing to aim for better and trying her best to solve any problem or crime. As Alfendi himself commented, Lucy possesses proven good intuition, and displays great curiosity and willingness to learn new things. She is also very forthright in her expression, being very honest and direct about her thoughts and feelings, to the point of coming across blunt or incorrigible in certain situations.
Additionally, she sometimes displays a level of stubbornness and recklessness, often jumping to conclusions and forging ahead without considering the risks and dangers. Alfendi once described her as a "daredevil" - a statement worded without compliment.
Lucy exhibits a strong sense of empathy, even when threatened with grievous danger or spoken to rudely by those with which she empathizes. As Alfendi would later mockingly proclaim, Lucy never fails to 'see the good side of people'. This was later displayed clearly as she believed Diane was simply driven insane by her father's death despite literally receiving death threats from her and held captive before.
Lucy also has a tendency to rely more on her instincts and gut feeling, as seen by how she tend to investigate cases. This is both her weakness and strong suit- as this is how she was able to reveal the truth about the Forbodium killings despite not being there four years ago and aided her in defending Alfendi's innocence, but also at the same time, withholds her from solving cases quicker as she often uses her feelings more than actual evidence- Alfendi often had to remind her to pay attention to case notes and witness statements. This is the opposite to some of Alfendi's deducting techniques, as he often uses logic more and relies concrete evidence, but similar to Lucy, he also sometimes, uses his gut feeling and deduction. He even encouraged Lucy to listen to her gut feeling during the earliest cases, saying that it is an important part in investigation- and he was proven right later.
Case 000 (Freshly Baker)
Some time prior to her assignment to the Mystery Room, Lucy took her detective exams, in which she did poorly, but was able to pass, blaming it on a bad balti the night before. On her first day on the job, Lucy met with Scotland Yard's Deputy Commissioner Chan, who scolded her for not paying attention to him. She apologised for her mind being elsewhere but suggested that the good weather was a good omen for her new career. Unimpressed, Chan told her that she had been assigned to a 'back office' that could be closed down at any time, but she replied that the said location was where all the unsolved crimes were sent - 'where the real stinkers get cracked'. Commissioner Barton appeared, agreeing with her and adding that she had been assigned to a very talented inspector whose deductive powers were known to be among the best in the Yard. Thanking the officers, she rushed off, leaving the two men behind.
Case 001 (The Hand Sandwich)
Upon arriving at the office, Lucy found no one inside, and resolved to practice her pinpointing of suspects. In the middle of her performance, however, she found herself face to face with Alfendi Layton. As Lucy apologized, she introduced herself as his new assistant, telling him that she wanted to learn a lot and that she hoped he'd show her the way. Thinking of him as her mentor, Lucy dubbed him "Prof". However, Alfendi questioned the name, telling her that his father had been a real university professor. Unperturbed, Lucy continued to refer to him by the name, prompting him to tell her that he hadn't yet decided whether she had a permanent position as his assistant or not. To that end, he gave her an ongoing case with which he could test her abilities and she prove her worth to him.
Case 002 (The Bungled Burglary)
Florence Sich, a woman working on the forensics department came into Alfendi's office and at first thought Lucy was a woman Alfendi brought with him to work, but later, Lucy introduced herself as Alfendi's new assistant. After he showed up, Florence later told them about a case that has been bothering her and requested them to solve it, even making a deal with Alfendi- if he fails to do so, she'll call him "Prof", just like how Lucy does, for the rest of his days.
Lucy discovered about Alfendi's split personality for the first time here. After finishing the investigation, Lucy and Alfendi confront the killer. Tired of the culprit's relentless denying of her involvement, Potty appeared for the first time, in which Lucy finally got to know about Alfendi's disorder. Towards the ending of the case, Florence Sich, the forensic that requested the case warned Lucy about the possible dangers if she ever finds herself alone with him, as how Florence said she'll "rip her drip and run like the wind". Lucy replied by jokingly telling Florence about how she'll come to work in running shoes the next day.
Case 003 (A Murder Staged)
Lucy described to the player that this case is possibly the highest-profile case she and Alfendi (referred to as the Prof) have ever worked on, as the victim is a famous actress.
Justin Lawson assigned her and Alfendi to investigate the death of Gloria Blaise. After completing investigation, Lucy and Alfendi interrogate the culprit, in which Potty showed up again on the last minute to get the criminal to confess. Lucy found quite the trouble mid-investigation, as the prime suspect was attracted to her and relentlessly tried to win her over. Which greatly annoyed Lucy to a great extent, turning him down repeatedly even when he offered her a high-paying job to work for him, preferring to work with Alfendi instead, much to Roscoe Strapping's dismay. After the interrogation, Lucy later remarked to Justin about Potty's violent tendency to give terrifying threats, in which Justin merely replied that she couldn't "blame that man for having a sense of humour", but nevertheless, quietly asked Lucy to report to him if she ever finds Alfendi mumbling strange, unfamiliar names/locations.
Case 004 (The Walking Corpse)
Lucy described this case as a unique one, as it had four human suspects and 'summat else'- an apparent demonic force. She ended her monologue by telling the players that "Demons are real, oh. Aye."
Dustin Scowers asked Lucy and Alfendi to solve this case, primarily because it involves his older brother- Doug Scowers, who's arrested as a suspect. He managed to talk them into taking this case in, telling them that the only way to help save his brother is to prove his innocence on the murder of Dr. O'Logie.
Lucy, along with Alfendi, was both shown to be highly skeptical of supernatural things, she often argued with Chico Careta mid-investigation about the true existence of demons which Careta himself is a firm believer in. After Lucy and Alfendi solved the case, Dustin later informed them that the police couldn't get any actual useful information from Chico, and that "getting any new info from him is as likely as me (read: Dustin) getting a promotion". Mariana Etista, a suspect that was supposed to be brought in for questioning disappeared and turned out to be a fake identity, and in reality, she and Chico weren't childhood sweethearts as Lucy assumed- she arrived at Chico's village merely six months ago before the murder occurred.
Case 005 (The DJ's Swansong)
After Lucy and Alfendi listened to the apparent accident that happened on the radio, Sniffer came in and reported that they have received dozens of calls, asking if Dwight Dread is alright. Sniffer predicted that Dwight must already be dead as they talked, and he was proven correct. And so, Sniffer assigned them to investigate Dwight's murder.
Lucy later befriended one of the suspects who was apparently Lucy's age as well. Unfortunately, one of the suspects, a middle aged man implied interest in her. But he was later proven guilty anyway after extensive investigation. This is the second incident where the male suspect finds Lucy attractive and attempted to sweet-talk her (Roscoe Strapping, however, openly declared that he wanted to woo Lucy, while Mike De Bonair was more subtle and more of implied attraction to her, but both men directly and openly described Lucy as pretty). In the end, she and Alfendi solved the case anyway. This is one of the rare cases where she and Alfendi had to solve a multiple-murder case.
Case 006 (Kiss Goodbye)
On a rare event, Commissioner Barton himself handed out the work personally to her and Alfendi. He asked them to solve a particularly puzzling case- a mafia family of four were found murdered on their hideout. No suspects could be found as the group of sailormen who found them literally landed minutes ago from Africa when the bodies were discovered.
The two could only find one person who is most likely involved with the killings- a key witness who disappeared. However after a brief investigation, they received a call informing them that they've found the witness; a delivery boy named Uttar Mistry who was the last person to see them alive. Although Lucy and Alfendi couldn't find the culprit's identity immediately, they were able to pinpoint the method of their murders. Lucy finally discovered about the Jigsaw Puzzle Killings for the first time. Alfendi explained to her that the killings are a series of quite scandalous murders with all victims found with a piece of jigsaw puzzle next to their body, and that the killings are kept secret from the media to prevent a mass hysteria outbreak.
Case 007 (The Mystery Rooms)
Hilda Pertinax, an interpol agent and an old friend of Alfendi's asked him to investigate an abandoned house directly as "a personal favour" in order to find and catch an escaped criminal who the police believed to be responsible for some crimes that has occurred.
She attempted to tap into their conversation, but was later caught by Hilda and reprimanded for doing so. This case is the first one of three cases in which Lucy had to solve a case on the actual crime scene instead via the reconstruction device, and the only case which Lucy did not solve a murder-related case, rather on a hide-and-seek type of case to find an escapee.
After exploring the abandoned house, Lucy unlocked a hidden basement where they found Diane Makepeace, daughter of Keelan Makepace, a criminal who was wanted by the Force years ago. Diane revealed herself to be the true identity of Mariana Etista, the girl responsible for manipulating Chico Careta into murdering O'Logie and the murders of Severino Agonni and his men. Diane later escaped, with Alfendi restraining Lucy from going after her, knowing that Hilda's people would have surrounded the place by then.
Case 008 (Ham and Cheese)
Hilda asked Lucy where Alfendi could've gone after she received an invitation from Diane Makepeace to meet her at Forbodium Castle, the same place where Alfendi got shot and nearly died years ago. Lucy tells her that she does not know where. Justin later joined the conversation and revealed that he had gotten an invitation as well. The two deduced that Alfendi must've gone by himself to the castle. Justin ordered Lucy and Hilda to go after him while he stayed behind to coordinate officers to aid them in the mission.
Hilda told Lucy to stay close to her to ensure safety, but the two women got separated once they got inside the castle. Diane subsequently captured Lucy and forced her to solve an old case where the suspects and the victim are all wearing animal masks and their identities are disguised. Diane threatened that she'll kill her by pumping gas into the room and Hilda as well if she fails to solve the case, and later instructed her to press the red button once she figured out who killed Pig (the victim, who was apparently an agent Diane murdered in order to reenact her father's murder) before disconnecting from the intercom.
After solving the case, Lucy later learned that the case Diane told her to investigate was one of Keelan's earliest murders, in which Alfendi apparently worked on years ago. Diane gave her the real files from the case and Lucy discovered that someone destroyed a vital evidence that could've gotten Keelan arrested earlier. Diane told Lucy that Alfendi killed Keelan and destroyed evidence, which Lucy did not immediately believe. Diane released Lucy anyway and she left the room but not before advising Lucy to not trust Alfendi Layton.
Case 009 (Good Cop, Bad Cop)
The last and final case of Mystery Room.
Lucy was just talking to herself about her disbelief of what Diane just said when she suddenly heard a loud gunshot from above. Lucy entered the room, only to find Alfendi tied up and blindfolded. To her horror, she found Diane dead, laying in a pool of blood. Hilda rushed into the room and questioned Alfendi. After she managed to convince Lucy of Alfendi's involvement, she was prepared to turn him in when Potty made an appearance, but it didn't take long before Justin appeared. He gave Alfendi a chance to explain himself and untied him, in which Alfendi used the opportunity to host an investigation while simultaneously reopening Keelan's murder. Potty assumed control for most of the case, even having Hilda and Justin as suspects. But Placid regained control, but instead of supporting what Potty said, she said the complete opposite- he admitted to the murder much to Lucy's disbelief and shock. Still in denial, Hilda later talked to Lucy and revealed the truth of Alfendi's personality; Potty was actually the true Alfendi, Placid was the secondary personality that emerged after the incident where Alfendi got shot and fell into a coma. With this newfound information, Lucy finally made up her mind and decided to resume investigation while trying to convince Alfendi himself that he is innocent. She managed to compile evidences and enough statements and eventually exposed the true mastermind of the entire Forbodium scheme, succeeding in exonerating him from all charges and bust Justin as the true murderer.
Later, towards the ending of the game, she asked Alfendi about his meeting with Justin in his prison cell, which both Placid and Potty remarked as disastrous and horrible, and that Justin refused to say a word about his true motives. Alfendi revealed to Lucy about Keelan actually only being responsible for 15 murders- Justin was the one who put puzzle pieces in the remaining 11 murders, getting Keelan to take responsibility. Lucy subsequently managed to convince Alfendi to ditch paperwork and to go outside with her for a while, as seen by the denouement of the game.
- As revealed in a conversation between herself and Dolly Hollerday, Lucy is 22 years old during the events of Mystery Room.
- Her speech pattern consistently replaces the word "was" with its plural "were". An example of this is "I were miles away" as opposed to "I was miles away". It is inferred from Lucy's diction and vocabulary in the game that she speaks with a Yorkshire accent. This is strongly implied as she is shown using Yorkshire slang, such as "summat", which is slang for "something", for example.
- Lucy originating from the English county Yorkshire is also backed up by a line she says in case 007 when she mentions favouring Yorkshire tea.
- While Lucy's hair matches a light brown, in the case 'Who Killed Pig?' if you choose Cat as the culprit, Diane Makepeace will call Lucy a 'dozy ginger', suggesting Lucy's hair is supposed to be red, or at least reddish.
- In Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy, Katrielle Layton is twice depicted writing a letter to Lucy, indicating that the two know each other and are friends.
- Similar to Alfendi, Lucy's relationship with him was also questioned by some characters. Dolly Hollerday openly asked her about this in Case 005.
- Alfendi referred to her twice as "my dear Lucy" on Case 003 and Case 007, which prompted some characters to question their relationship.