Master Fu is a 186-year-old healer and the Great Guardian of the Miraculouses, who guards them when not in use. He gave Marinette Dupain-Cheng and Adrien Agreste their Miraculouses to stop Hawk Moth and his villains' evil-doings. With the Turtle Miraculous, when inhabited by Wayzz, Master Fu can transform into a turtle-themed superhero.
Before Season 1
Sometime afterwards, Fu came to Paris and became acquainted with Marianne Lenoir whom he fell in love with. He told Marianne about the Miraculous, the Miracle Box and his duty as the Guardian. However, during Paris' Nazi occupation and Fu planned to flee to England to protect the Miracle Box. He and Marianne, who had decided to stay behind and resist, parted ways.
In "Ladybug & Cat Noir (Origins - Part 1)", Master Fu was with a client when Wayzz interrupted him, telling him that he could sense the Butterfly Miraculous. Master Fu tried to transform in order to get it back, but due to his age, he could not. Instead, he went to search for two new Miraculous holders.
He stopped by 12 Rue Gotlib street in the 21st arrondissement and crossed the street. A car was barreling down the street, as it had the right of way. Marinette Dupain-Cheng pulled him out of the car's way before she left for school. Seeing her bravery, Master Fu left the Ladybug Miraculous in her room. He then pretended to trip and lose his cane outside near Collège Françoise Dupont. Adrien Agreste helped him up. Seeing Adrien's kindness, he left the Cat Miraculous in his room. He decided that these two would be the best users. He was only wrong once and it wouldn't happen again, or so he hoped referring to himself.
In "Stoneheart (Origins - Part 2)", the next day after the Stonehearts were taken care of, Master Fu and Wayzz watched Marinette and Adrien as they left the school. Wayzz approved of them as the next wielders, Master Fu stating that they were made for each other.
In "Princess Fragrance", Master Fu was visited by Marinette who brought a sick Tikki to him. In the process of healing the kwami by using a gong and reading energies, he reminds Marinette that she must be patient. He playfully asked her what sort of cat Tikki was, and she told Master Fu Tikki was a rare breed from a far away kingdom. After Tikki was fully healed she asked how he did it and he tells her it was an Ancient Chinese secret.
In "Animan", Master Fu was observing one of the animals at the zoo in the background.
In "Gamer", Master Fu was seen watching Adrien and Marinette while they were in the park behind a lamppost.
In "Antibug", Master Fu was in the lounge area of Le Grand Paris Hotel until Chloe and Sabrina were cosplaying Ladybug and Cat Noir that caught his attention.
In "Volpina", Master Fu is seen in his shop meditating as he sensed Marinette's arrival.
In "The Collector", he officially meets Marinette and explained that he chose her to wield the Ladybug Miraculous because of her willingness to help others. From Tikki and Wayzz he also explained that he came from the Order of the Guardians, a group of people whose job it was to distribute the Miraculous for the good of humanity. But when Marinette asks about the book, Master Fu detailed that the Miraculous Book is an instruction manual on all the powers of the Miraculous which he was able to partially translate. He also pointed out besides the book, Master Fu also lost the Peacock and Butterfly Miraculouses.
He concluded that whoever had the book and the two Miraculouses was believed to be Hawk Moth. But when Master Fu asked Marinette how she found the book, she lied by saying she found it on a bench. When Marinette decides on who Hawk Moth could be he advises her to be careful, but after her evidence was proven false (unaware that she was right) Master Fu understood why she lied because he knew that Marinette was afraid that the one she loves was Hawk Moth.
That's when Master Fu realized that for them to defeat Hawk Moth, they would have to trust each other, to which Marinette agrees. Then to solve her friend's problem, Master Fu took pictures of the spellbook so Marinette could return it to Gabriel Agreste.
In "Robostus", after defeating Robostus, Master Fu was visited by Marinette who had questions about the combined powers of the Ladybug and Cat Miraculouses. The guardian explained that whoever uses the Miraculouses' combined powers will obtain the power to alter reality; the ability to make a wish. But he confidentially warned Marinette that since the universe must stay in balance, for every wish a price had to be pay. And, he tells her that she and Cat Noir must never lose their magic jewels.
In "Sapotis", sometime ago Master Fu taught Marinette all the secrets of the Miraculouses. Then, he was drinking tea when he heard someone knocking at the door which happens to be Marinette. When she explains that her Lucky Charm told her to come to his shop, he took it as a sign that Marinette's Lucky Charm is telling her the heroes need help. As Master Fu goes to the Miracle Box he hesitated on the idea of letting another Miraculous out but was assured by Marinette that she and Cat Noir were very carefully with their powers. Afterwards, he showed Marinette all the Miraculouses and advises her to choose wisely in picking a trusted ally. He also told her that when the mission was over she must return the chosen Miraculous to him as it was too dangerous to let any of them out for long until they learned all the Miraculous secrets. When Master Fu asked Marinette if she knew of someone, he watched as she took the Fox Miraculous and said yes. Once the mission was over, Master Fu put the Fox Miraculous back in the box and praised Marinette for making the right choice.
In "Syren", after Marinette returned the Fox Miraculous Master Fu noticed that something was troubling her and she spoke of hiding secrets from Cat Noir and the guardian says things will be revealed in time. At the time he was cooking up a magical potion for modifying the kwamies' power but forbid Tikki and Wayzz from following them under the warning of what would happen if they were captured with that knowledge. Through reading the spellbook Master Fu almost figured out the recipe for unlocking "Aqua Mode" but lacked the final ingredient. After testing it on Wayzz, he realized the potion didn't work.
After the streets became flooded because of Syren, Master Fu and Wayzz retreated to the roof, along with the ingredients and Miracle Box. After being found by Marinette he expressed sadness over not finding the last ingredient, but Marinette refused to give up. Thinking about using a real tear of joy, Marinette made Master Fu tear up in laughter at her jokes, and when the tear was added to the potion it was a success. At Marinette's request, Master Fu found Adrien on the rooftop and promised to explain everything and gave him the Aqua potion.
Afterwards, he gave Marinette a list of the magical potions telling her the ingredients could be contained in anything. He approached the Agreste mansion as Adrien's substitute Chinese instructor officially meeting Adrien as Plagg introduced him as the Guardian of the Miraculous. He then gave Adrien a box of potion filled Camembert.
In "Anansi", he was approached by Marinette who explained that Cat Noir was about to have his ring taken and Nino couldn't hold off Anansi for long. Refusing to let that happen he instructed her to choose a Miraculous and a trusted ally. When Wang found out that she needed his, he and Wayzz allowed her to use it and after Anansi was defeated Marinette returned the Turtle Miraculous and Wayzz back to him.
In "Sandboy", he was reading a book in his shop until he fell asleep, after Sandboy turned Paris into a living nightmare. Wang Fu was woken up by Marinette but covered with nightmare sand causing the guardian to face his nightmare: the pressure and guilt of his past mistake. He instructed Marinette to transform but she couldn't and was informed of Tikki's whereabouts, which was not good because he said that there was no way for them to communicate with the kwamis while they're in their magical world. Driving away the ghosts with a stool he was approached by Wayzz who apologized for not telling him but noticing their predicament Master Fu says they'll talk about it later.
After Sandboy's defeat he was slightly angered by what happened, but understanding that Marinette and the kwamis had good intentions Wang forgave them and said to come to him the next time they need something.
In "Style Queen", Master Fu and Wayzz are approached by Plagg who told them what happened to Adrien. Then, after Marinette arrived she tried to explain the same thing but he already knew and told Marinette that her partner lost his ring. When Plagg offered to help, Master Fu said it was out of the question aware of how reckless he was without an owner and tried to remind the kwami of the destruction he had caused previously. Once again he allowed her to pick a Miraculous and trusted ally then watched Marinette take the Bee Miraculous.
In "Queen Wasp", from watching the live feed of the fashion show Master Fu wasn't fazed at all that the Bee Miraculous ended up with Chloé. He assured Wayzz that Marinette would do no such thing and had faith in her that she would fix her mistake. After Queen Wasp was defeated the Bee Miraculous was returned to him.
During "Malediktator", Master Fu was doing math with an abacus until Marinette came in and explained that the titular villain had turned her partner into a cat. Shocked he says that she shouldn't have left Cat Noir on his own being at Hawk Moth's mercy, which Marinette agrees but also said the Lucky Charm led her here. Knowing not to disobey the charm he allowed Marinette to choose a Miraculous and an ally, witnessing her take the Bee Miraculous again. Master Fu was cautious after hearing the events of "Queen Wasp", but was assured by Marinette on how to properly use it.
After Malediktator's defeat, Wang Fu knew that Marinette took a big risk with Chloé and was still cautious that she was the right choice. Marinette spoke of how Ladybug made her a better person and that same could be said for Chloé, hearing a noble answer he supported Marinette's choice.
In "Catalyst (Heroes' Day - Part 1)", upon hearing the news Master Wang knew there would be a day when Hawk Moth would discover the unbound limits of his powers. After being approached by Marinette once more he offered her to choose an ally and watched her take the Bee, Fox, and offered his Turtle Miraculous too, wishing the heroes luck to get the Butterfly Miraculous back.
In "Mayura (Heroes' Day - Part 2)", after Hawk Moth's defeat Fu was given back the three Miraculouses placing the Bee and Fox Miraculouses in the Miracle Box and wearing the Turtle Miraculous again. He thanked Marinette for a job well done.
During "Backwarder", aware he won't live forever, Master Fu sent Wayzz to get Marinette and once she arrived. He told her that if anything happens to him she'd have to take care of the Miracle Box and the new guardian. And asked her to deliver a letter to his friend Marianne realizing he waited too long to confess his love and thanked Marinette for accepting the task.
Once Marianne was deakumatized and Fu was feeling better they met at their spot. He apologized to her for waiting so long and from her he learned that Hawk Moth got closer to finding him. Aware that Marianne was in danger too she said it was her turn to hide, with that he wanted to express his love for her but was stopped until she came back. Master Fu expressed hope Ladybug and Cat Noir would defeat Hawk Moth and the two would be together.
In "Miraculer", he loaned out the Fox and Turtle Miraculous again when Ladybug and Cat Noir needed in defeating Destroyer and was given back the jewels when the job was finished. Seeing the threat Miraculer posed Wang once again told Marinette of the circumstances but he found out that the whole team was needed he let her take the Bee, Fox and Miraculouses again. However, like Marinette Wang Fu was also aware that Chloé revealed her identity and questioned about her. She was sure that Chloé was up to the task wanting to save her best friend with the whole team they were able to deakumatized Sabrina and stop Mayura from taking Bee Miraculous with the danger over all three were returned to Master Fu.
In "Oblivio", Wang received a call by an amnesiac Marinette asking her if something was wrong and was informed that her memory was erased by Oblivio as well as asked if her partner was with her. She said that Adrien was and figured out the that the two discovered their identities but wasn't too worry since the magic ladybugs would fix everything anyway. With Marinette's phone running out of power he quickly asked the duo if their kwamis were with them and was informed that the "red one" was with them. Wang told them of their kwamis names and how to retransform. However, he was told by Adrien that Plagg flew away and that Adrien couldn't transform without him but before he tell the pair more Marinette's phone ran out of power ending the call.
In "Party Crasher", Wang attended the all boys party for Adrien at the Agreste mansion. While dancing on top of the cooler hiding the Miracle Box, he nearly falls but is caught by Kim, but soon Party Crasher crashed the party. He with everyone else escape but stayed out of sight but watched Ladybug's and Cat Noir's battle when the heroine was caught Wang held Cat Noir saying he needs help. With that he signed the Snake Miraculous to Luka, the Horse Miraculous to Max and his Miraculous to Nino but seeing them all get captured along with Cat Noir. Wang thought of one Miraculous that could help with it being so special he decided to trust what saw in Kim with the Monkey Miraculous. But seeing Kim and Xuppu bonding through making funny faces he suspected that he made a bad choice and yet seeing him come through in the end with the other heroes in defeating Party Crasher. Wang believed he was the right choice after all and had retrieved all the loaned Miraculouses.
In "Desperada", once again he allowed Marinette to pick a Miraculous along with a trusted ally. Upon seeing her take the Snake Miraculous, Wang told her that this Miraculous was very powerful and that it must be used by someone whose wise enough and not tempted to use time manipulation for their own personal gain. He was happy that Marinette knew of the perfect person for the job and after Desperada's defeat the Snake Miraculous was returned to him.
In "Startrain", after Ladybug's and Cat Noir's late night fight, Master Fu has the Fox Miraculous returned to him and thanks Marinette for a job well done. When he heard of Marinette's class field trip from Tikki as well as Marinette's choice not to go under the knowledge of Hawk Moth causing trouble while she's away. Solving the solution he gave Marinette the Horse Miraculous in case if there was a villain in Paris. Agreeing that she and Cat Noir deserved to have some fun.
In "Kwamibuster", he was relaxing in his shop until being approached by a panicked Marinette saying that her and Cat Noir's identities were jeopardized and yet Wang reminded her of the consequences. To help her Wang allowed Marinette to pick another Miraculous for herself until she rescued Tikki.
In "Feast", hearing of Alya's latest discovery from Marinette, Wang was aware she'd figure the truth out sooner or later. But he soon became horrified at the sight of a sentimonster that he thought was long gone and explained his mistake. Refusing to let Adrien and Marinette suffer he took their jewels and decided to leave Paris to draw the creature away. In trying to escape and being informed by Wayzz he saw that his disciples will do anything to help him even without their powers and was encouraged to follow their example but put Wayzz in his Miraculous. When Ladybug and Cat Noir were back into a corner and realizing his kwami was right Wang stared down his own sentimonster revealing himself to Hawk Moth but returned the heroes jewels.
In trying to find the creature's amok, Wang told Ladybug that his staff was part metal and to hide. While the heroes were in the belly of the beast Wang and Wayzz continued to run until they couldn't anymore believing this was the end, he thanked Wayzz for his service. But seeing Ladybug and Cat Noir defeat the creature he thanked them and seeing that the Order of the Guardians had returned Fu was happy he could return home someday. Seeing Marinette's courage and acknowledging her as a full fledged Ladybug he felt it was time to pass his role of guardianship to her.
But he also realized with Hawk Moth still out there and knew his identity his job wasn't over. With the shop no longer safe Wang decided to move but remain in Paris assuring Marinette that he'd always be there when they needed him.
In "Ikari Gozen", Wang was working at the cinema to hide his identity s from Hawk Moth. When Ladybug arrived he knew that she sought out help once more and allowed her to choose a temporary miraculous and an ally. Then, saw her take the Dragon Miraculous and after Ikari Gozen was defeated it was returned.
In "Heart Hunter (The Battle of the Miraculous - Part 1)", some time prior he wrote a letter to Marinette about the trials of losses as well as loving life and moving on putting it in his locker at the train station. Afterwards, on a bench in the park Master Fu was looking at a photo Marianne. Then was approached by Marinette as Ladybug and lent her the Dragon Miraculous but soon he was attacked by Hawk Moth and Mayura with no choice Wang transformed into the Jade Turtle. Despite putting up a good fight he used the power of Shell-ter to protect himself but was captured.