As Will competes in a swimming competition, tension arise between her and Matt with an old friend of Matt's from summer camp being her competitor. Meanwhile, Nerissa has her heart set on another Heart. In response, the W.I.T.C.H. do the unthinkable: they release Phobos from his cell to even the odds against her.
The episode contains the following tropes:
- All Webbed Up: Cornelia wraps Halinor with the algae from the pool.
- All Your Powers Combined: With Nerissa's control over the former Guardians broken, the sorceress elects to absorb the women into the Seal, thereby gaining access to all the Guardians' powers.
- Bittersweet Ending: The girls are able to break the former Guardians out of Nerissa's spell... only for her to absorb them into the Seal and gain their powers. Despite this, breaking the spell is what pulls Nerissa away, making her narrowly miss out on claiming the Heart of Aridia. While Phobos doesn't manage to snag the Seal, as Will notes, this is the first time they've had Nerissa running scared from them.
- Breath Weapon: The first thing Nerissa does after absorbing the former Guardians into the Seal is to breathe a torrent of fire.
- Deal with the Devil: Unable to take the Seal of Nerissa by force, W.I.T.C.H. employ the aid of Phobos: as a member of Meridian's royal bloodline, he's the only person able to take the Heart of Meridian, and by extension the Seal, without Nerissa's permission. Knowing the risk this presents, Will promises Phobos his freedom on the condition he swear by Kandrakar to return the power of the Hearts of Meridian and Zamballah to Elyon and Kadma respectively. This becomes important later...
- Emerging from the Shadows: When Vathek, Caleb and Will arrive to the prison, Caleb says that besides Elyon, there's only other living heir of the Meridian throne who could take the Seal from Nerissa, and that person is Prince Phobos, who emerges from the shadows of his prison cell in amusement.
- Enemy Mine: Phobos is forced to join forces with the good guys against Nerissa out of self-preservation.
- Evil-Detecting Dog: Well, dormouse, as Mr. Huggles for some reason refuses to sleep with Matt and goes to Phobos. It is later revealed this was because the latter two were glamoured as each other.
- Evil Is Petty: While posing as student "Phillip" at Sheffield Institute, Phobos does things like handing Taranee the wrong beakers in chem lab so that the mixture will blow up in her face, while staying at Matt's house, he hogs the bed and makes Matt sleep on the floor and when Cornelia gives him a plate of macaroni with cheese by lunch at school, he dislikes it and throws it on Cornelia's face.
- Glamour: After a close call attack by the former Guardians, Phobos, believing the girls incapable and incompetent, glamours Caleb, Blunk and Matt as himself and himself as Matt in an almost successful attempt to take the Seal.
- Graceful Loser: After her "loss" to Will, Mandy congratulates Will saying she won fair and square, which makes the latter to feel guilty. Even when Mandy does win to Will, she downplays her success and says she just got lucky.
- Green-Eyed Monster: Will gets jealous when seeing Matt talking to his old friend Mandy from summer camp although their relationship is indicated to have been platonic. This is what pushes her to cheat in the swimming competition by using her Quintessence to win in their first race, and she's certainly not happy when she sees "Matt" kissing Mandy on the hand before their next race.
- Idea Bulb: Will makes a nearby sign's bulbs flash with her powers when realizing they can't take the Seal of Nerissa by force because the core of it is the Heart of Meridian, which Elyon was tricked to giving to Nerissa willingly, thus they need help from another living heir of the Meridian throne, Phobos.
- I Kiss Your Hand: Phobos, (disguised as Matt) kisses Mandy on her hand before her swimming race to annoy Will. The real Matt is shocked to learn this.Matt: (to Phobos) You kissed Mandy?
- "I Know You're in There Somewhere" Fight: Hay Lin to her grandmother's Altermere (who she still doesn't know is an Altermere), both physically and emotionally trying to remind her that she and her friends are Guardians, a force of good. It doesn't work on Yan Lin, but it does make Cassidy to briefly remember her team are Guardians, though it goes unnoticed. Later, at the fight in the pool, Cassidy remembers she used to swim there in her high school years, and Irma uses her power to influence minds to free her and the other old Guardians for good.
- Literal Metaphor: When Raythor tells Phobos that making a deal with the Guardians is beneath the former, Phobos replies that the cell he's imprisoned at the time is also beneath and around and above him as well.
- Little "No": When Nerissa is alerted by her Seal that one of its spells has been broken, she wonders which one was until she realizes in anger that the Guardians have released Phobos from his prison to take her seal.
- Nice Job Fixing It, Villain!: Nerissa apparently gave Cassidy some will to have a conversation. However, it also enables the latter to slowly break free and her friends from Nerissa's control.
- No, You: When Will comes to visit Phobos in prison, he remarks that she reeks of desperation, and she retorts that he reeks before getting to the point.
- Out-of-Character Alert: What makes it really obvious to the viewer that Phobos and Matt have switched places is that "Matt" makes a disparaging comment to Will to the effect that second place is the first loser and "Phobos" tells her she did great and not to listen to him, although strangely the Guardians don't catch on. Also, the time that "Phobos" seemingly acts affectionate towards Cornelia (which disgusts her) is actually Caleb.
- Pungeon Master: During her seduction of the Heart, Nerissa and the Heart of Aridia partake in a few puns throughout the episode.
- Red Alert: The Seal of Nerissa is able to alert her when its spells are broken by others. This lets her know the Guardians freed Phobos from his prison (as Elyon locked him up back in "J is for Jewel" while wearing the Seal necklace) and also that they managed to free the rest of C.H.Y.K.N. from her Mind Control.
- Teeth-Clenched Teamwork: The Guardians are not exactly thrilled with the idea of working with Phobos, but desperate times call for desperate measures.
- Troll: At one point, Phobos and Matt are glamoured as each other as part of a secret plan to mislead Nerissa. Phobos takes the opportunity to mess with Will (who's unaware of the switch) by kissing Mandy on the hand in front of her with a smirk, making her to literally spark with jealousy.
- Wham Shot: When Nerissa arrives to confront the guardians, both of them are shocked by the appearance of three Phobos. They turn to be a disguised Caleb, Matt and Blunk.
- Your Approval Fills Me with Shame: Phobos is the only one who sees Will using her powers to cheat and win the race and compliments her on her underhanded tactic. This very clearly upsets her and the guilt sets in quickly.