Laetitia is a woman that teams up with Lupin to steal the Bresson Diary in Lupin III: The First. She is the granddaughter of famed archeologist Professor Bresson as evident through her passion for archeology and was the adoptive granddaughter of Professor Lambert.
Appearance[]
Laetitia has partially tied back chestnut-colored hair and blue eyes. She dresses in a mustard-colored jacket, tan shorts, and walnut colored high heel boots.
The only other outfit she is seen wearing is a fake museum guard outfit in the beginning of The First, which was part of a plan to steal the Bresson Diary for the Nazis.
Profile[]
Laetitia is Professor Bresson's granddaughter. She was named Laetitia after her mother, who is Bresson's daughter, following a tradition where the women in the family was named Laetitia.
After giving Laetitia one of the keys to open the diary, the Nazis come to Bresson's house to find the diary, eventually killing him after they fail to obtain it. Her parents escape from the Nazis in a car chase but they crashed and die, Lambert finds her alive inside the car but only steals her the key. And after a few years he adopt her just to use her as a tool to find the diary.
She works for Professor Lambert for years as the professor made a deal with her, if she succeeded doing the tasks, the professor would let her get on Boston University in Archeology Department. The professor tasked her to steal the Bresson's diary, which was presented in a museum. Disguising as a police officer, she unmasked Lupin who showed up to steal it, warning Inspector Zenigata.
She gets the diary but Lupin snatches it from her hands in a small chase where she slips and falls but Lupin rescues her.
Without the diary she returns home and Lupin is there waiting for her, and she hides in the restroom to speaks with Lambert and they make a deal to give him, Lupin and the diary.
She and Lupin make a good relationship, she tells him about her mother is named Laetitia because all the women of her family are named as, and her parents dead when she was a baby, and in a moment he flirts with her, almost kissing her.
They arrived to Lambert's plane where they find out the way to open the diary using their own keys together, and using her name (Laetitia) as the password.
She apologizes to Lupin for the trap and hands him over to Lambert.
After hearing a conversation between Lambert and Geralt, she finds out that they want to use the eclipse as a weapon and is thrown down of the plane and Lupin jumps after her without any parachute, they are helped by Fujiko.
In a moment before the group arrives near Teotihuacan, where the eclipse is, Lupin confesses to her that she is not Lambert's granddaughter, her real grandfather is Bresson and also Lupin I (Lupin's grandfather) was his partner designing the diary's lock. And each one had one of the two keys.
They get the way to arrive where the eclipse is, with Jigen, Goemon and Zenigata's help. And after a few traps and a magnificent physical challenge skill, they get the eclipse but they are captured by Geralt and Lambert who take Laetitia to discover how to use the weapon.
The cave falls apart and Lupin and the others escape and go to save Laetitia.
Laetitia tries to stop Geralt and Lambert's plan but Geralt tries to shoot her but Lambert gets the shot and died.
She and Geralt arrives to Brazil to the Ahnenerbe base where Geralt meets the Führer and Laetitia tries to kill him holding a gun on him and Geralt, but she keeping away there by Jigen. Zenigata explains her that they arrive there and capture all Ahnenerbe men thanks to the Interpol's help.
While Lupin fights Geralt, Laetitia watches helplessly from below, and is relieved to find Lupin alive.
Laetitia hugs Lupin seeing him safe and sound, he tells her that eclipse doesn't exist anymore and when she was trying to confess her feelings, Fujiko appears to tell them goodbye, but at the second try, Jigen and Goemon show up to pick up Lupin, saying that Zenigata is after them.
Laetitia asks Lupin if he won't take her with him, but he said she can go anywhere now that she is not tied to an old boss anymore, and that coming with them wouldn't be a nice idea. Lupin tells her that he will meet her in 5 years, giving her the letter to a conference in the Boston University of Archeology as a farewell.
Notes[]

The first part of the Bresson Diary's password mechanism, saying the password only uses the letters A, E, I, L and T.
- Her name is officially translated as Laetitia rather than Leticia. This is to prevent confusion from another character called Leticia, a dolphin who appeared in Lupin the Third Part III. It is also because "Laetitia" fits the Bresson Diary's password, which uses five letters (A, E, I, L, T) and is eight characters long.
- It is safe to assume her theme song is Gift, as multiple variations of the track plays in a lot of her scenes (most notably during the sunset scene in the middle of the movie) and because the track "Young Passion of Laetitia" plays Gift's main melody.
- Laetitia’s birthday is on March 22. This is the only time when a date for her birthday was given.
- Laetitia's full name is derived from two Arsène Lupin characters: Dolores Kesselbach, also known as Letitia von Malreich from '813', and Bresson, the thief of the golden chimera from its hiding place in the "Jewish Lamp" from 'Arsène Lupin vs. Sherlock Holmes'.