Gareth Lestrade was a Scotland Yard Inspector where he worked with Sherlock Holmes.
According to Holmes, Lestrade was "the best of a bad bunch" among those few Scotland Yard detectives who agreed to work with him. Although Lestrade was, in Holmes's words, "utterly adequate" as a detective, Holmes was often scathing about his limitations, so the two men were not close, despite their professional respect for each other.
Because Holmes always preferred to work anonymously, he allowed Lestrade to take the credit for solving their cases, and eventually Lestrade became addicted to the glory that accrued. Lestrade himself said that those days were the best time of his life, though he denied being a glory hound, and instead simply reveled in the satisfaction of being a successful detective.
|After Holmes was incapacitated by his drug addiction, Lestrade found himself struggling to work on his own and, according to his superior, DCI Hopkins, began to cut corners for the sake of closing his cases. This came to a head when Lestrade investigated the murder of Mary Pendry, whom her husband, Lawrence, claimed had been killed by a home intruder. Lestrade suspected Lawrence himself, but could not prove it. Lawrence's father, Warren Pendry, a media mogul, employed his newspapers, and a substantial amount of money, to "paint a very ugly picture" of both Lestrade and Scotland Yard, forcing Lestrade's superiors to suspend him. When Warren died, Lestrade took revenge at his funeral by threatening the mourners with a grenade, besmirching Warren and then disappearing. This resulted in Hopkins calling Holmes to London to find Lestrade.
|Holmes finds Lestrade in a pub, waiting for a security guard to go off duty so he can raid a stash of money left behind by Holmes. He convinces Holmes to help him with the Pendry case before turning him into Scotland Yard. Sherlock calls Watson to an abandoned theatre where Lestrade is hiding and while reviewing the crime scene photos, Sherlock ponders why the Pendrys have a bottle of milk when Lawrence is lactose intolerant and Mary was a devoted vegan. Sherlock also wonders why one of four bronze masks is slightly lower than the others. He gains access to Pendry's home by showing him a fake murder/suicide note from Lestrade. At the theatre, Sherlock and Watson reveal to Lestrade that Pendry used a plastic gun made with a 3D printer which he then melted in a milk bottle filled with acetone. A scorched nail behind the mask was used as a firing pin which Pendry hid by using it to hang the lower mask. Lestrade is exuberant until Sherlock points out they have no solid evidence to arrest Pendry.
|After Sherlock gets a list of all 3D printers sold in the last 18 months, he has Lestrade review the list and tries to apologize for enabling Lestrade's craving for glory. Lestrade interrupts as he recognizes Nicholas Gint on the list who was Pendry's handyman and had an alibi the night Mary was murdered. They go to Gint's flat where Lestrade says that if Sherlock wants to make amends, he'll give him the credit for the case. Lestrade kicks Gint's door in and they find him dead on the floor with one of Gint's kitchen knives in his chest. Sherlock finds evidence linking Pendry to Gint's murder and Pendry is arrested at his mansion. Lestrade stands outside Pendry's home grinning. Sherlock tells Lestrade that in order to break his addiction to fame, he is not to take credit for the arrest and if he does, Sherlock will discredit his involvement. The next morning, Sherlock and Watson see Lestrade on TV claiming the credit for Pendry's arrest. Watson observes that Lestrade called Sherlock's bluff and as Sherlock expresses the peculiar emotions he's feeling, Watson points out the emotions are those involved when one cares about an addict. ("Step Nine")
|After a bomb explodes at a restaurant and kills staff from the Dept. of Labour (DoL) and a bank where Richard Balsille is CEO, Holmes and Watson are forced to work with Balsille's "security czar", who to Holmes' revulsion, turns out to be Lestrade. Despite Holmes' having saved his career and kept Lestrade from jail, he is arrogant and challenges Holmes to see who can solve the bombing first. Lestrade has an aide, Miss Truepenny and orders a helicopter to take them to the hospital to interview the survivors. Together at the hospital, they question Michelle Forrester, a DoL undersecretary. Seated at the end of table, she escaped with minor injuries and mentions a seating plan which Holmes asks for. Holmes and Watson leave Lestrade to employ deductive pseudo-science, a "deep dive", with Forrester.
|To Lestrade's concern, Holmes wants to question Balsille after finding a unidentified guest named Jacques St. Teton at the hotel adjoining the restaurant. Balsille confirms one of his executives who was killed, Larry Iver, was a rising executive who had enemies but when Holmes see a book Balsille wrote entitled "Teton", he calls Lestrade out of the office. Holmes threatens to confront Balsille about being at the Griffin Hotel as St. Teton and committing the bombing that killed Iver to eliminate him as a contender for CEO. Lestrade has Truepenny get security and has Holmes and Watson seen out. Holmes and Watson discover Lestrade checked in as St. Teton but he lies that it was Balsille. As Watson sees him out, he tries to recruit her and she pick-pockets his phone. The next morning, Holmes tells her he found evidence on Lestrade's phone that Balsille had him monitoring Iver who was plotting to oust Balsille as CEO.
|Lestrade finds a suspect, John Bowden, so Watson meets him at the 11th Precinct where she returns his phone. Holmes is waiting for Lestrade in his hotel room and shows Lestrade evidence of his monitoring of Iver. Confronted that he's a suspect in Iver's murder, Lestrade tells Holmes that Balsille has sex with many different people who he pays off with whatever they want. Lestrade does the approaching and arranges the hotel room. Embarrassed, he kept this from Holmes and knows that if Balsille's secret was revealed, it would ruin them both. After Holmes finds the home of a serial bomber nicknamed Aurelius, he meets them there upset that Holmes didn't inform him. Holmes rebukes Lestrade for complaining instead of developing his deductive skills like Watson. Aurelius is found to have died before the restaurant bombing.
|Banging on The Brownstone door, Lestrade enters and accuses Holmes of leaking Balsille's secret. He shows them a blackmail threat complete with details of Balsille's encounters and demands to discretely make hundreds of stock trades. From the date the trades are demanded to be made, Holmes deduces who's behind the bombing and blackmail. The criminal is a woman who was one of Balsille's conquests and since he won't provide details to the police, which will prove her guilt, Lestrade does and is fired by Balsille. Lestrade arrives at the Brownstone and asks if he can stay and witnesses Holmes' successful experiment with two former fighting roosters, Romulus and Remus. ("The One Percent Solution")
|Several weeks after being fired by Balsille, Lestrade is still at the Brownstone where Romulus has taken a dislike to him. Although he has offers from investigation firms, he can't decide. After being mugged, Watson confronts him about drinking at the Brownstone. He admits he's lost his confidence and can't be a special detective without Holmes. Watson gives him the police case file on muggings that have happened in the area, hoping to rebuild his confidence. Lestrade tracks down the mugger to his home and knocks him out. His finds a rooster feather on the floor and believes this was a setup by Holmes. He confronts Holmes who admits to a setup (even though there wasn't one) and Lestrade announces that he's accepted a position with the Irish National Police. ("Ears to You")|
- His phone password is the last year that Tottenham Hotspurs won the F.A. Cup (1991). ("The One Percent Solution")