Thelonious is the henchman of Lord Farquaad and possibly the executioner, as he's the one who tortures Gingy by breaking his legs and dunking him in the milk, as well as threatening the Magic Mirror by suggesting Lord Farquaad to break it. He is also the one who suggests Lord Farquaad choose Fiona, telling him to choose number three while holding up two fingers.
He is seen at Shrek and Fiona's wedding and at Shrek's Karaoke Dance Party, where he seems to have become friends with Gingy; his former torture victim.
Thelonious appears at the end sitting in the audience of the movie theater in Far Far Away.
Video Game AppearancesThelonious appears in Shrek Super Party as a playable character. His largest desire in the game is to take a nice vacation away from the torture chamber. If you win the game as him, he'll be seen in a makeshift island at the chamber.
Thelonious appears in Shrek Smash and Crash Racing as one of the eight unlockable racers in this game. His kart is the Black Horse and his personal item is a giant stone age axe.
Thelonious appears in Shrek: Fairy Tale Freakdown as an opponent and unlockable champion. His attacks include throwing hand axes, charging at his opponent and punching.
In Shrek: Reekin' Havoc, Thelonious is a boss fight in the Duloc castle, where he has been named the new king after Farquaad's death.
A portrait of Thelonious appears in Fiona's cell in the Shrek The Third video game.
Thelonious isn't really as villainous as he seems. When Fiona and Shrek kiss during her wedding with Lord Farquaad, Thelonious writes "Aawww" on one of the signs used for telling the people on how they should they react.
On Shrek 4-D he kidnaps Fiona and takes her to the raft to kill her, but he is doing it only under the command of Lord Farquaad's Ghost. He accepts Fiona punching him in the face. When she kicks him in the groin, he falls overboard and she apologizes to him. He fell from the waterfall but grabs the branch below it. When Fiona, Shrek and Donkey fall as well, he shows his good side by catching them all in one hand while still holding the branch with his other hand until the branch breaks. When Dragon comes to help them, she takes all of them, including Thelonious.
- He is one of the several characters who appeared in the first film only to never show up in future installments.
- It is unknown where he went after Duloc was abandoned.
- Thelonious appeared in a poster in the Shrek 4-D queue-- a parody of the film Terminator 2: Judgement Day.
- In an early draft for Shrek the Musical, he was the Captain of the Duloc Guards. He also led other captains named after pop culture characters (Captain Kirk from Star Trek, Captain Jack Sparrow from Pirates of the Caribbean, and Captain Kangaroo).