At the greenhouse, the wealthy property owner named Zenzou Sunada is showing Conan, Ran, and Sonoko the golden barrel cactus and it blooms flowers after 50 years.

In the hospital, Sakota is lying on the bed to get his treatment done. There's a high possibility that Sakota was struck with bare hands. The Nagasaki police took in the karate girl with a black belt, Ran, who was the main suspect to the station for questioning.

Conan, Ran, and Kogoro must've slip through time (not literally). Ran won a prize at a shopping district lottery, they go to Nagasaki.

Conan, Ran, and Kogoro went to Ohama Coast from Beika Street for two hours and they are going to have fun surfing at the beach.

The wife, Sumika, tried to scare the husband to cure his hiccups.

The Detective Boys are invited to the Konno residents for a barbecue as a thanks for solving a case for them earlier. When the couple argue, the children grow concerned. Later, the husband cannot find his cell phone so his wife goes with him inside to look.

After visiting the three, Conan explains the robber in the video was left-handed and only Takayo Tegawa fit that description.

Conan stops feigning his sleep and tells his kidnapper who is really she.

Arriving at Katshitsuka's home, Ran receives a phone call from Masumi. The phone call receives noise which Tooru deduces to indicate the house is bugged.

Kogoro prepares to meet with the client Kei Katshitsuka. While waiting, he receives mail of Katshitsuka who changes their meeting location to a local restaurant. There, Kogoro realizes the cell phone address is different from the first message he received from the client.

The mystery of Darkness Tower is revealed by Conan.

The Detective Boys meet Nanami Kyoudou, who's grandfather, Seitarou Kyoudou is the one who built "The Black Tower", rumored to have no entrance and treasure hidden within. Later, they visit her house.

A second DNA test with sterile samples reconfirms the rough DNA match leading Conan to a conclusion. Conan tranquilizes Kogoro and reveals Banba and Kamon are opposite sex identical twins. The secret phone calls were to a medical consultant with the final phone call confirming the genetic match. Learning of his, Kamon clasped her face into her hands, scratching some skin off, and committed suicide. In the aftermath, Amuro pays Kogoro to have him as his apprentice.

At Ristorante Sundayrino, Raita Banba and Hatsune Kamon are getting married. Kogoro, Ran, and Conan are also there. Everybody is having a great time with them. Later, Kogoro, Ran, and Conan are introducing themeselves to Kamon at the table. Ran heard that it was love at first sight for Banba and Kamon. As the night progresses, Banba receives a 'Goodbye' text message from Kamon. Outside, suddenly, Kamon's car exploded, right before Conan's eyes.

Mio was attacked by Karashima but attacks back in self-defense.

The guard named Zenkichi Ooka is threatening two people to keep giving money to him. At night, Conan, Ran, and Kogoro came from the store after they had delicious spring rolls.

At night, Hiroshi Yagisawa and his dog, Coeur are taking a walk in Beika Street. Coeur sense something strange so Coeur is showing Yagisawa that she found the dead body in underground passageway.

The Detective Boys wish to capture a few beetles to bring to school, and as a result, visit Agasa's old friend in the mountains. The Detective Boys manage to find a bunch of beetles at night, but return to find Namatame injured. Namatame's last words are "Miyama Stag Beetle" before losing consciousness.

Conan completes his investigation and realizes who the murderer is.

When Ran, Sonoko, Sera, and Conan are walking, they receive a phone call from Ran's father Kogoro, who asks her not to bother cooking dinner for him as he will be gone for the night.

Chiba is unable to recall Naeko's face though notes his familiarity. During the investigation, Conan realizes the culprit's motif and has the police let the suspects leave.

The Detective Boys discover officer Chiba's has been vandalized with a threatening word. Realizing is the culprit is the same person who has been on a vandalism spree that month, the Detective Boys push Chiba into investigating it with his first love

Conan, Ran, and Sonoko are invited to the opening ceremony of a chocolate shop that is supported by the Suzuki Group. They meet a woman named Mayuko Sakura, the shop producer. Next they meet a man named Yukihiko Tsujimoto, the chocolatier and he's Mayuko's fiancé. During Tsujimoto's show, the fire breaks out in the shop, killing Tsujimoto. Was this a terrible accident or a planned murder?

Conan realizes the kidnappers invaded Agasa's home too quickly and deduces they have visited recently; Agasa reveals three pairs of customers have expressed interest in the vase.

The Miracle of Excalibur is the twelfth OVA of the anime and manga franchise Detective Conan. The plot is based on Gosho Aoyama's short story "Excalibur."

Professor Agasa has recently posted a video on a popular website, asking for someone to evaluate an old vase he found in his attic.

Conan and Heiji's investigation leads them to realize how Ikuro and Serika were murdered.

Conan and Heiji resume their investigation while Ran and Kazuha gossip about Shinichi's confession towards Ran.

The police arrive and their investigations reveal the baumkuchen was cut evenly into eight pieces and that only one of the piece was poisoned.

Heiji reads a letter he received from an already dead man and old acquaintance of his mother, design company president Kouhei Wakamatsu, who was killed a month earlier in his Karuizawa villa.

Heiji and Kazuha visit Tokyo where the two part ways. A murder occurs at the restaurant Kazuha is in, forcing Kogoro, Ran, Sera, Heiji, and Conan to investigate.

Conan declares Mitsui is innocent since she was witnessed leaving Miku's room; Sawaguri inferred the culprit crossed over from the balcony and left by his room. As for Miku's death, Conan explains she was mimicking the suicide of the main character in her book. Sawaguri becomes distraught as a result and is taken in by the authorities.

Sawaguri, pleased to have another detective to find the culprit, obeys his requests to take pictures of the hostage's books which were autographed by Miku. During the course of the investigation, the authorities lose the chance to snipe Sawaguri after Ran closes the curtain as she believes Shinichi can find a solution to prevent any deaths. Miku's blog post reveals her last three visitors were from an elephant, a fox, and a rat. Conan explains the animals were based on the hostage's professions: The elephant is Sumika Nihei, due to her husband's seal designs is similar to an elephant's tusk; Shinobu Yuchi is the fox since she is a bakery and her food is colored like a fox's coat; and the rat is Tamami Mitsui whom is a stonemasonry which is gray like a rat's coat. In response, Sawaguri prepares to kill Mitsui.

Isao Sawaguri came to the Mouri Detective Agency and brought together three female novelists he believe are responsible for his younger sister Miku's death the previous month. Isao threatens to blow up the Agency unless Kogoro reveals to him the truth about his sister's death and reveals her murderer.

After investigating the room, Sera declares the culprit.

Ran, Sonoko, and Conan are on the bus ride to Haido Hotel. Sonoko felt like that someone touched her butt. She caught the guy in the blue hat and accuses him that he's the pervert. The guy in the blue hat tells Sonoko that he's not a pervert but Sonoko thinks he's lying. So she told Ran to beat him up. Ran does as she says so she kicks but the guy in the blue hat blocks Ran's kick with his leg.

With poison only on the victim's thumb and forefinger, the case becomes confusing. What evidence in the victim's possession will lead them to the culprit?

Conan is back home at Mouri Detective Agency. Kogoro is on the phone with Ran but suddenly got shocked that Ran is going to sleep over at school during night time because everyone's going to practice karate.

The Detective Boys stall for time while trying to discover the truth about Masao's parents without alerting them.

Conan has a cold and fever. Then he got a video call from Haibara. That video call contain about a boy who always lie.