- "Luckily, my men responded with their usual calm and bravery."
- ――Trouble Kelp
Trouble's appearance in the books was not described, but the graphic novels show him as being stocky and more well-built than his brother Grub Kelp. He has cropped dark hair, dark purple eyes and is about 2ft 11in (3ft in stacked shoes) as mentioned in Artemis Fowl and the Atlantis Complex.
Before Book Events
Not much is known about Trouble's history. In Artemis Fowl: The Eternity Code, it was said that five years ago, he was nearly hit by a plane over London. Since then, all flights involving airports in cities had to be approved personally by Foaly.
In Artemis Fowl, Trouble leads LEPretrieval One into Fowl Manor, but was easily brought down by Butler along with the rest of his squad. Trouble was the second casualty in Butler's counter-assault. He returns to the house after the bio-bomb has been released to check for bodies and retrieve the ransom, though he does not get much further in than the doorway, having been struck with sorcery sickness, a side effect of entering a human dwelling without invitation.
In Artemis Fowl: The Arctic Incident, Trouble takes command of the LEP forces during Root's absence. He is seen with his brother stuck in a phone booth during the B'wa Kell uprising. They make a run for it into the emporium, where Trouble orders the remaining forces to retreat. He also arrives in Chute E37 in time for Holly to show him the batteries which the goblins have smuggled in.
In Artemis Fowl: The Eternity Code, Trouble briefly discusses his brother Grub with Holly Short during a lockdown of Haven. He is also mentioned casually throughout the book.
In Artemis Fowl: The Opal Deception, Trouble is an LEP Major, promoted from his previous rank of Captain. In the beginning of the book, he is described by Commander Root as a more hands-on Major, which "might be what the force needs." He also secures chute E37 for Holly Short and Julius Root to enter. At the end of the book, Trouble is sent in a supersonic attack shuttle to apprehend Holly Short. He is given orders to shoot her down from Ark Sool, but refuses, instead giving her a chance to explain things to the LEP.
Trouble also appeared in the mini-story "LEPrecon" in The Artemis Fowl Files, and nearly loses his magic permanently after being kidnapped and brought unwillingly into a human dwelling by Julius Root's elder brother, Turnball Root, during an above-ground initiation for Holly Short. He risks his own position in the LEP when he defends Holly's unauthorized actions to rescue him and Commander Root.
In Artemis Fowl: The Time Paradox, Trouble Kelp is promoted to the rank of Commander, replacing Ark Sool. In Artemis Fowl: The Atlantis Complex, Foaly says that Trouble is Holly's boyfriend, to which Holly responds indignantly that Trouble is not her boyfriend and that they had only been on one date. It was meant to be kept secret, but Foaly had leaked this little tidbit onto his site www.horsesense.gnom. Trouble is also shown to have a major dislike towards Artemis Fowl II and frequently calls him 'Mud Whelp'.
He played a few roles in the first book and is a more major character throughout The Opal Deception. He has a younger brother named Grub Kelp, a corporal in LEPretrieval. The brothers are extremely different in every way, as Grub whines over everything, acting very childish, and Trouble is an expert in the tactical areas and a strong leader. He is often embarrassed by his younger brother's actions.
It is implied that he and Holly Short are/were engaged in a (albeit somewhat awkward) romantic relationship. When they first met (The Artemis Fowl Files) he is skeptical she would even make it into LEPrecon, but over time the two become friends. In The Atlantis Complex it is revealed they had started dating. In The Last Guardian, Trouble is revealed to be dating Corporal Lily Frond (although it is stated that it would not last).
Trouble has gone on three dates with Holly, with one ending with both of them being thrown out of a crunchball match.
He was involved in the siege on Fowl Manor during the first Artemis Fowl, though him and his LEP retrieval team were quickly defeated by Butler. Trouble Kelp disobeyed a direct order from the commander, Ark Sool, when ordered to fire at Holly's ship in the Opal Deception. He did not feel that Holly could have killed former LEP Commander Julius Root, so gave her time to explain. Though he did not fire, he was ordered to take her into custody.