Experiment 624 was the 624th genetic experiment created by Jumba with Hämsterviel's funding. She was designed to turn individuals and experiments from good to evil by singing her siren song. 624 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.
All of the experiment pods were released and scattered across the island of Kauai.
At an unknown point after this, Experiment 624 was activated and captured by Gantu.Angel", Lilo and Stitch were playing in the town when they suddenly noticed Gantu seemingly trying to capture 624, named Angel, when in reality Gantu was deliberately leading her to Lilo and Stitch in order to trick them into taking her in, which was part of his evil plan. Just then, Angel came out of nowhere and bumped into Lilo.
Lilo scolded Angel and told her to watch where she was going, but the latter just growled at Lilo and fled. Stitch, however, was smitten by Angel and chased after her. He soon found her in an alley and became attracted to her. Angel then licked Stitch, who immediately fell in love with her. He then managed to convince Lilo (who was already suspicious of Angel) to let Angel stay with them.During her stay, Angel began charming Stitch, who developed a crush on her. Lilo became increasingly paranoid while Angel did this, and restricted her to sleeping in a basket instead of with Stitch.
Sometime later, Lilo consulted Jumba to find out what Angel's primary function was. However, before Jumba could warn Lilo about Angel's powers, Angel sang into Jumba's ear, causing the latter to revert to evil and cover up for her.
After Lilo and Stitch left Jumba alone, he allowed Angel access to his experiment database. Unbeknownst to them, Angel was working for Gantu, who had sent her to successfully seduce Stitch and lure him into a trap.The next morning, Angel woke up to see Stitch proposing to her with a bouquet of flowers. Angel was flattered by this, but then attempted to revert Stitch to evil as well. However, this failed due to Stitch being created after her, although he complimented her singing.
Angel soon left the home with regret for Stitch and reported back to Gantu, while reverting several rehabilitated experiments to evil along the way. Confused but undeterred, Stitch pursued Angel around the island, attempting to woo her in various ways. She eventually lured Stitch to Gantu's hideout, where Gantu and the recaptured evil experiments lurked inside a concealed ship.
At the hideout, Angel revealed her true colors, but began to feel guilt over betraying Stitch. When the now-evil experiments were about to finish Stitch off, Angel realized she really did have feelings for him, and turned the experiments back to good before Kixx could land the fatal blow.
The experiments then escaped the hideout, while carrying Stitch triumphantly above their heads. However, when all seemed well, Gantu captured Angel and fled with her, despite Stitch's best efforts to protect Angel.
In "Remmy", Angel was one of the experiments in Lilo's dream.In "Snafu", Experiment 625 was able to trick the captive Angel into singing her song backwards (to "turn him good") while it was being recorded by him. Gantu then planned to play the recording backwards on the island to revert all of the rehabilitated experiments to evil, but the plan failed due to Snafu stealing the recording.
Meanwhile, Lilo and Stitch launched a rescue mission on Gantu's ship to free Angel and the other captive experiments, but were foiled by Snafu. However, Stitch's love for Angel gave her the strength to break out of her containment orb and free Stitch and the others. Lilo, Stitch, Angel and the freed experiments then narrowly escaped the ship, and Stitch and Angel left on a date shortly after.
The first 624 experiments, including Angel, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben and Gantu arrived before the experiments could be destroyed.
Angel participated in the following battle between the experiments and the Leroy clones using her karate skills to defeat and knock Leroys out, particularly when a group of Leroys attacked her boyfriend Stitch.
However, the Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song "Aloha Oe", which caused the Leroy army to shut down due to the original Leroy's fail-safe.
In the Stitch! anime, it is shown that Angel has become an international singing star, who appears in the anime series more periodically than the original series. Though she appears more frequently, her general attitude has shifted to that of a spoiled celebrity, which is logical as she has undergone approximately a decade of fame. There is evidence to this in several episodes. Upon her first meeting with Yuna, they were on bad terms apparently, but eventually put their differences aside. Stitch is madly in love with Angel and she shares the same feeling. However, it is seen that she instantly left Stitch for 627 when he was disguised as a prince, Reuben when he was modified by Hämsterviel, and Jack.
Angel is shown to be seductive and deeply enamored by Stitch. Sometimes she is good, and sometimes she can be downright mean. Though since she has been turned good, her nice side shows a lot more. She has a very feminine voice and likes to flirt in front of the other experiments. She is 100% in love with Stitch, as she grabs onto him and just tries to be near him at all times. She acts like a sister to both Stitch and Reuben, so she can be very protective of them. She can and probably will get annoyed if she can't find Stitch or if someone is picking on her "brothers", though she acts more strict toward Reuben than Stitch for reasons only she knows. She's always thinking of places her and Stitch can go and spend some time together.
She sort of acts like the mother to all the other experiments and doesn't mind showing it. She hates people who try and make trouble around her new home.
Angel is a pink, shapely female koala-like experiment with a strong feminine resemblance to Stitch, with two long tendril-like, violet-tipped antennae, violet-tipped ears with light pink insides, small eyelashes, a thin white V-shaped symbol on her chest which resembles cleavage, purple fingernails and toenails, slightly larger chest puffed out and two violet/lavender back markings; one is similar to Stitch's on the back of his head and the other is an upside-down heart on her back. She has large, dark purple eyes that appear as black and seem to be slightly larger than Stitch's eyes. She has long, purple eyelashes. She does not possess the extra arms that Stitch does. She also has big ears, and her nose is purple and smaller than Stitch's. Her antennae are about half her body height; these she can use as prehensile limbs (in her namesake episode "Angel", she used them to push a button; she is also seen manipulating them in fanart, thus it can be assumed these antennae make up for her former lack of second arms). Her head is usually at a tilt because of the way she speaks. She has light pink spots of fur around her eyes and a purple spot on the top of her nose. She stands 3 feet 2 inches tall and weighs 95 lbs. She once wore a collar with Hämsterviel's phone number on the tag. She wears a purple spacesuit with a diamond consisting of a dark purple border and white center on her chest and each of her sleeves and patches consisting of a dark purple border and lavender center on each of her legs, black belt with dark purple square buckle, both black collar, cuffs, and anklets.
Angel's song causes anyone who hears it (including rehabilitated experiments created before her) to turn evil. Also, when Angel's song is sung backwards, it will have the opposite effect (turning evil people and previous experiments to good). Angel is also shown to be highly athletic and skilled with karate. She can use her antennae as prehensile limbs, and uses them to reach distant objects or operate mechanisms (such as a button). She is able to speak full English as well as Tantalog, her native language (with a soft Scottish accent).
Angel's song goes as follows:
English translation: Heed me, you are in my power. Henceforth, nothing shall be too cruel or too abominable for you. You cannot escape.
The lyrics of Angel's song when sung backwards are as follows:
Like Stitch, Angel has pads on her hands and feet that produce a sticky stubstance which lets her scale walls and ceilings, a very flexible skeletal system, allowing her to put her feet into her mouth and roll into a ball, and retractable claws on her front and back paws, but unlike Stitch, she lacks an extra pair of retractable arms. She's strong enough to shatter the sealed glass containers that experiments had been captured in by headbutting them; however, the true extent of her strength is unknown. Angel depends mostly on laser-whips/swords, but is also capable physically with acrobatic reflexes and antennae. She is naturally heat resistant to toxins and extremely durable. She can swim, unlike Stitch, but she has no means of underwater breathing.
Experiments who were created after Angel are immune to her song.
- Angel is the first and only experiment to not be regarded as one of Stitch's relatives (due to her role as Stitch's girlfriend).
- Angel is a non-playable character in the game Lilo & Stitch 2: Hämsterviel Havoc for Game Boy Advance. In the game, Dr. Hämsterviel has "re-evilled" her and uses her to turn the other experiments back to evil. It is unknown if Hämsterviel forced her to sing or if she took the job by choice, because she turns back to good after she sees Stitch. It is implied that Angel is rescued at the end of her part in the story, so unless she was later recaptured by Gantu, the game is not canon to the animated series.
- Angel appears, along with several other Lilo & Stitch characters, in a parody of the Disney Channel Original Movie High School Musical, which was broadcast as part of the High School Musical: Around the World one-year anniversary special.
- Angel is a parody of Lorelei the Siren, as her song is an evil in the guise of beauty, much like the Sirens of ancient myth.
- In the Finnish version of the television series, her name is Seireeni, meaning Siren.
- Angel's pod color is white.
- Angel is described by the experiment computer screen as, "Experiment 624 Primary function: Turn the people and experiments from good to evil with a siren song".
- Due to a continuity error, the fur pattern on her back is inconsistent. In "Angel", it is an upside-down heart. In "Snafu", it resembles Stitch's, but disappears in some scenes. In Leroy & Stitch, she does not have one at all.
- Angel's body and antennae appear in the game Jumba's Lab.