The Holmes' Revelation Arc is one of climatic entries in the series. Not only does Shinichi return for some time, he also (kind of) finally confesses to Ran he loves her.
It's a dream come true for Conan when he finally gets to go to London, home of his hero, Sherlock Holmes. However, the fun is cut short when a little boy requests help. Meanwhile, Ran is questioning her love for Shinichi when a woman tells that love is zero.
 Characters introduced
 Holmes' Apprentice
Kogoro, Ran, and Conan find a cat belonging to a rich British woman who offers to pay their expenses on a trip to London so Kogoro could share his detective stories with her friends. To get past airport security, Haibara gives Conan two antidotes to the APTX 4869 for the trip and the way back home. At the Holmes Museum, Ran calls Shinichi asking him if he wants a souvenir from London. His weak reaction causes Ran to angrily hang up. Outside the museum, a kid named Apollo Glass asks to see Holmes' Apprentice to solve a code that will prevent a person from being murdered. Conan offers to solve the riddle by posing as Holmes' Apprentice. Apollo reveals a strange man gave him a note containing seven coded riddles, declaring someone in London will die if it is left unsolved. They learn from the police that many children have received the same code which Conan speculates to mean a large number of people will die. Conan and Agasa separate themselves from the group as they attempt to decode the riddles.
 Love is 0
Ran, feeling upset as she believes Shinichi does not return her feelings, is confronted by Apollo's sister, pro tennis player Minerva Glass. Minerva then parts ways with Ran advising her that "Love is Zero" (a pun referencing that the term "Love" is used in Tennis to denote a zero score) and would never amount to anything no matter the effort. Ran calls Shinichi for advice on the riddles. Conan, tells Ran the first riddle "A rolling bell rises me", refers to Big Ben and accidentally reveals he is in London. Realizing Ran will discover Conan's true identity if she finds him, Conan and Agasa flee from her. Conan becomes cornered in a phone booth and is forced to take the antidote, APTX 4869, for the return trip and confronts Ran as Shinichi. Ran confesses her pain of liking Shinichi who is indifferent to her feelings and runs away as is left chasing after her.
The next day, the police reveal the identity of the man who created the note, Hades Sabara. Kogoro and Ran decode the riddle "My portion is like a chilled boiled egg like a corpse" which refers to City Hall. There, they find many dolls with "Mazarin Stone" written on their shirts where when beheaded, reveals the letter "T". The riddle "I finished up with a whole pickle" refers to 30 St Mary Axe where they found scratched up pens labeled as Dancing Men reveal the letter "N". At Big Ben, Ran and Kogoro find an arrow pointing to a drain where The Valley of Fear of fear is inscribed. They deduce from the story that something had been sunk in the river, and find a drain cover with the letter "A". Apollo leads the two to the next riddle, "Now I remember to ask a cake to celebrate in advance" referring to St. Bride's Church where they find letters entitled, "A Scandal in Bohemia". Soaking the letter in water reveals the letter "S".
 Code Break
Shinichi has returned to Conan again. However Haibara had only given him two pills, he will have to figure something out. Gradually deciphering the note handed out by the criminal, Conan discovers that the place where he plans to attack will be at Wimbledon, where Minerva Glass is supposed to be playing. When they reach the stadium, the criminal has already entered, and since they do not have tickets, they stay outside. However, they can watch the game from a screen that is located outside of Wimbledon. Minerva appears to be losing.
 Grass Court Queen
Minerva is losing because she's writing a message in braille by hitting the ball on the lawn, which Conan understood. He convinces Apollo to give him his ticket. When he enters the room, he tells Minerva that he can help. Minerva believes it and keeps writing. The message said that the mother of Minerva was going to die. Conan focuses on finding Hades and asks Minerva to lengthen the game. Minerva gets to play and the party has to decide in the tie-break.
 0 is Start
Conan meets his parents and give a ticket. After locates Hades with the help of Minerva, Bystanders see Conan as "Holmes Apprentice" and compliment him and then Hades sees him. Before even pressing the button to trigger the bomb, Minerva throws a tennis ball and hits Hades. After that, Conan then takes the ball and kicks it. It hits Hades and he got stopped by the police. Minerva wins the match and meets with Ran. She says Shinichi told her that the zero is also a starting point. Haibara gave Shinichi's parents an antidote because she knew that he would use it.
 Manga to anime changes
- In the manga, when Conan accepts Diana's invitation to visit her in London, Azusa Enomoto mentions in an obviously stunned manner that Conan can speak English, an observation also made by Ran.  In the anime, while still taking place in the Cafe Poirot, Azusa is completely omitted from the scene. Instead, Kogoro takes over her role of noticing Conan's ability to speak English. 
- In the manga, Hades Sabara's past is elaborated on in more detail. Shinichi reads online that after his mother died, Hades invited the acquaintances hounding him for money to his house where he slaughtered them all. One week later, he went to the home of the friend who suggested he invest in the stock market; not only did Hades murder the entire family, but he ripped out all of their hearts. While the online source did not explain the reason behind such brutality, Shinichi speculated that his mother's serious disease could have been related to the heart.  The anime only states that Sabara killed these people.  The omission is likely due to the dark nature of the crimes and the gruesome background panel accompanying the story of Sabara's past in the manga, an image which was likely too graphic for animation.
- It should be noted that characters inside the arc were named after the Roman and Greek gods.