If you heard the word “Aho!” I know who’s popping in your mind, who else but these two Kansai-ben’s, Hattori and Kazuha. They have a major roles in the DC series as evidenced by their appearances on dark contact arcs but they mostly appear on special episodes.
So here are the cases where they are involved in:
↘Episode 48-49 The Diplomat Murder Case – Hattori Heiji’s first appearance. Heiji appears at the Mouri Detective Agency because he heard that Kudo (The famed “Detective of the East”) hangs out there and wants to meet him to find out just how good he is.
↘Episode 57-58 Holmes Freak Murder Case – Heiji signs up for a Holmes Lover’s Club in hopes of running into Kudo, despite the fact that he prefers Ellery Queen. The head of the Holmes Lover’s Club dies in a suspicious way after promising to give the first edition of ‘A Study in Scarlet’, the first novel Holmes appeared in as the prize for their game. He discovers that Conan is Kudo Shin’ichi after Conan knocks Heiji out and uses Heiji’s voice to solve the mystery.
↘Episode 118 The Naniwa Serial Murder Case – Heiji invites Conan, Ran and Mouri to Osaka to visit after having a dream of Kudo being stabbed in the heart and killed. He shows them the highlights of Osaka – Especially the food. Ran feels like she’s being stalked, only to discover that it’s been Kazuha following them around. A dead body falls onto the hood of the car they’re riding in, a victim of the serial killer that’s been stalking Osaka – leaving the victims with a wallet pinning their wallets to their hearts with a knife. Heiji and Conan pair up to solve the murder. Heiji gave Conan his omamori(lucky charm), which then stopped the knife attack, saving Conan’s life. Heiji is shot in the belly apprehending the murderer, but refuses to let the murder kill himself.
↘Episode 141-142 The Night Before the Wedding Locked Room Case – Heiji’s mother asked him to go to Tokyo as her proxy for the wedding of her friend since she can’t walk because of a broken bone. Kazuha tagged along because Heiji’s mom asked her to and so she can go shopping in Shibuya. The bride doesn’t seem all that happy to be married. After the butler is murdered in a closed room case, Heiji and Kudo worked together to solve the case and Kazuha is jealous of Ran, because her outfits keep matching Heiji’s. LOL
↘Episode 166-168 Tottori Spider Mansion Demon – Heiji gets lost and runs out of gas on the way to a mystery he was invited to solve. When Kazuha worries, he suggests that they may have to sleep outside, curled up together for warmth. She blushes, he’s clueless. They run into an American photographer, also lost. Heiji tosses his helmet at a passing car who didn’t stop, only to run into Mouri, Conan and Ran. The Spider Mansion has a history of people dying in the storage room, a former Temple to a slain Spider Demon, defeated by a Puppet Master. The victims are hung from the rafters, strings tangled around them like a Spider’s Web.
↘Episode 174 The 20 Year Old Murder Case – Conan figures out the answer to a riddle in the newspaper, winning he, Ran and Mouri a free cruise. A murder happens after they set sail and they discovered that there’s another detective on board – Heiji! The Detective of the West was invited to come, and given a stack of bills. He came to return the bills.
Heiji gets hit over the head and was tossed overboard.
↘Episode 188-193 Kudo Shinichi’s Desperate Revival – Conan was shot on the previous episode (with the detective boys) and Heiji comes to visit him in the hospital after Agasa calls him, it appears that Ran has figured out who Conan is. Conan doesn’t understand why Ran hasn’t said anything. Heiji deducts it’s because she’s waiting for him to tell her.
Kudo asks Heiji what would he do if he were in Kudo’s shoes. We don’t get an answer. During the school play which Ran was the lead princess, Heiji disguises himself as Kudo to throw Ran off track, making it appear that Conan and Kudo are in the same place at the same time. When a murder happens in the audience, Kazuha ruins this, seeing through the disguise easily. Heiji then helps Kudo with the deductions, acting as his assistant because they are in Tokyo.
After Kudo collapses, Heiji gets on the microphone and asks the audience to keep the days events secret because a murder at the school would start up rumours.
↘Episode 220-221 The Client Full of lies – Shizuka’s first Appearance. She does Kendo. She faces the murderer, who is wielding a katana. She stops an attack by catching the blade in her closed fan, trapping the blade and pulling the katana from the murder’s hands. She wants to know who this person is that Heiji’s spending so much time with and getting beaten up.
↘Episode 222-224 And There Were No Mermaids – Heiji receives a letter addressed to Kudo Shin’ichi, asking him to come to Mermaid Island, else they will be killed by the Mermaid. (In myths, eating a mermaid’s flesh is supposed to grant immortality) When they arrived, the yearly Mermaid Festival is going on, Kazuha won a sacred arrow that is supposed to grant it’s owner good luck and longevity but if you loose the arrow, you’ll receive a curse and die. There’s a murder that’s going on and during the course of the investigation, Heiji and Kazuha fell off the edge of a cliff. Heiji grabbed a branch and Kazuha, but can’t pull her up as well. She stabbed him in the hand with the arrow, wishing to pass the longevity to him, even if she should die.
↘Episode 238-239 The 3 “K”s of Osaka Case – Kazuha thinks that Heiji’s having an affair with someone because of all the suspicous phone calls he’s making to Kudo, asking if Kudo’s alone. Heiji invites Conan to the opening to the new ‘Osaka K3’ restaurant, because his favourite soccer player from when he was a child is one of the new owners.
↘Episode 263 The Osaka Double Mystery – Okita’s First Appearance in the series. Heiji’s parents invited Mouri, Ran and Conan to dinner in Osaka, which coincides with Heiji’s school Kendo championships. Heiji’s ranked 5 on his team, he’s the best fighter on his team and is supposed to fight his rival Okita in the final round. A dead body appears in the equipment room and while people rush off to inform the police it disappears. Only to re-appear in the shower room without anyone seeing it. Heiji leaves the tournament to solve the mystery. When the murderer attacks him with a katana, he stops a blow with his mobile (has an omamori on it). When the mobile is cut in half, he jumps and lands on the katana blade, defeating the murderer while standing there.
The second part. Kazuha leads the tour of Osaka this time, taking them to Osaka Castle to view the sights. While in there, they came across into five history fans on the ‘Eight Days of Taikou Hideyoshi’s History Tour’, visiting the places Hideyoshi did. While looking for Kazuha’s lost wallet at Osaka Castle, a burning man falls off the roof of the castle. His last act is to grab the umbrella Heiji is holding, giving a clue to a case from thirteen years ago that Heiji and Kazuha’s fathers are still attempting to close. Upon finding Heiji’s involvement with the case, Heizo punches him, which just enrages Heiji and encourages him to work all the harder at solving the case.
↘English Teacher vs Western Detective – Agasa-hakase calls Heiji and requests that he come up for a visit to help Shinichi. In the process, he accidentally stands Kazuha up, he invited her out to eat at a restaurant Otaki-han had recommended in Umeda. They visited Jodie-sensei, Ran’s English teacher, believing that she might be Vermouth, one of the men in black. A murder happens during the course of the visit, a dead body falling in front of them. Heiji notices that her accent is funny, she speaks better Japanese than she lets on. She points out that he excels at speaking english. He also pick pocketed the film she’d used to take pictures of he and Conan solving the murder.
↘Episode 291-293 Solitary Island of the Princess and the Dragon King’s Palace – Heiji was invited to be involved in a game show, “Detectives East-West Challenge” versus Mouri in Okinawa. The Island’s economy hasn’t been well since the last time they went to visit the islands (Mermaid Island) so the event was held to revive the Island’s economy. A some-of-twist-of-events happened.
↘Episode 323-324 Hattori Heiji’s Desperate Situation! – While meeting with Kusukawa, a former police officer under Kazuha’s father, Heiji and Kazuha are kidnapped and handcuffed in an attic in an attempt to force Heiji to crack a code.
↘Episode 325-327 Red Horse Inside the Flame – A series of Arson fires are breaking out in Beika that Heiji was asked to help solve by Kusukawa. When Ran hangs a Teruteru Bôzu (A doll that said to be preventing the rain to come) on the window to chase the rain away from Conan’s field trip the next day, Heiji pulls it inside, so Conan can’t go and will solve the mystery with him. While Investigating, Conan and Heiji notice a striking resemblance to a famous case by the Detective with the little Grey Cells.
↘Episode 345 Head-to-Head Match with the Black Organization – Heiji (being the proxy again) disguises himself as Kudo at a halloween party in hopes of catching the bad guys. Yukiko spent 6 hours getting the make up correct as for Conan he had something else to do. (THIS IS A MUST WATCH)
↘Episode 381-382 Whose Reasoning Show – Kazuha challenges Heiji that she can solve the case before he does. If she wins, they go to Takarazuka (a play). If Heiji wins, they go to Koshien (high school baseball finals). Along with Ran’s help she solved the dying message, but heiji won by solving the rest of it. Conan seeing how desperate the two girls to win showed some clue to them to solve the case but Heiji does all the blabber until he solved the case.
↘Episode 383 Miracle at Koshien Ball Park – While at Koshien, they received a supposedly lost cell phone but the cellphone isn’t lost, it’s a message. Unless they solve the riddles before time runs out, the entire baseball stadium will go up in flames, taking everyone with it.
↘Episode 406-408 Conan and Heiji’s Reasoning Magic – Kazuha asked Heiji to go to a Magic Show with her to explain the tricks to her. During the show, Ran and Kazuha attempted to save the magician when an escape trick goes wrong, After that they’re invited to dinner at the Magician’s Sensei’s house, where a murder happens. Heiji admits that he gets annoyed and has trouble concentrating on a case when Kazuha does something flirtatious, especially other guys, but can’t figure out why.
↘Episode 479 Three Days with Hattori Heiji – A contest between High School Detectives on a deserted island! Heiji represents the West and Hakuba Saguru represents the East but it’s not all fun and games when the teenage contestants start to drop dead. Heiji asked the pd-nim if Conan can tagged along (He is supposedly the representative of the East).
↘Episode 490 Hattori Heiji vs Kudo Shinichi: The Grand Deduction Battle – A Flash back when Heiji was 15 and on a ski trip with his school. Murder mystery involving the story of the Yuki no Onna (Snow Maiden). Heiji and Shinichi scrambled to solve the case, without ever meeting each other while their parents try help from the background.
Ahhh I almost spent 2 hours making this. It’s hard to backlog old episodes so forgive me if there are grammatical errors. I will check this again later for some missing episodes.