!!The 1981 film

* HeyItsThatGuy: Maggie Smith as Thetis, Burgess Meredith as Ammon, [[Film/DrNo the original]] BondGirl as Aphrodite (which doubled as a ParentalBonus when the movie was new), and, most of all, LaurenceOlivier as Zeus -- there's a reason ''Film/LastActionHero'' referred to him in this role.
* MoneyDearBoy: Part of the reason LaurenceOlivier was cast as Zeus. Probably the same with Maggie Smith.

!!The remake:

* HeyItsThatGuy:
** Solon, the Argos soldier with the most lines and screentime is played by veteran Irish character actor Liam Cunningham who has been in a billion Irish movies but is best known as [[Series/GameOfThrones Davos Seaworth.]]
*** Also, one of the other soldiers is The Hound.
** [[Film/HarryPotter Lord Voldemort]] is trying to get revenge on his brother [[Film/BatmanBegins Ra's al Ghul]].
*** Creator/LiamNeeson clearly loves playing those "grandiose deity" characters; he also famously [[HeyItsThatVoice voiced]] [[Film/ChroniclesOfNarnia a certain personification of God]] elsewhere. And for all of this, we love him.
** The only thing standing in his way? [[{{Film/Avatar}} Jake Sully]].
** Creator/LiamNeeson and Ralph Fiennes have fought [[Film/SchindlersList before.]]
** Draco was [[Film/CasinoRoyale Le Chiffre]] and Io is [[Film/QuantumOfSolace Agent]] [[spoiler:[[UnfortunateNames Strawberry]]]] [[Film/QuantumOfSolace Fields]].
** Perseus' adoptive father was [[Film/{{Inception}} Maurice Fisher]] and [[TheUsualSuspects Kobayashi]]. Who was in... so many movies he deserves his own trope for being the HeyItsThatGuy in so many movies.
*** His adoptive mother was the [[Series/DowntonAbbey American wife of a British lord]] and [[Film/OnceUponATimeInAmerica girlfriend of a Jewish American gangster]]. And she was KickAss's mother.
** [[Film/XMenFirstClass Azazel]] plays Acrisius/Calibos. And [[Series/StarTrekDeepSpaceNine Dr Bashir]] plays Hermes.
** Film/JackTheGiantSlayer has a rather larger role as one of Perseus' team.
** Apollo has later become [[{{Film/Immortals}} Zeus]] in that other crappy Greek Mythology movie. Thankfully, his career was saved with a great performance as Bard the Bowman in ''TheHobbitTheDesolationOfSmaug''.
** Andromeda is [[Film/DieAnotherDay Miranda Frost]] and [[Film/TheWorldsEnd Sam Chamberlain]].
* SoMyKidsCanWatch: Creator/LiamNeeson took on the role of Zeus because his sons thought it would be awesome.
* StarDerailingRole: For both Sam Worthington and post-production 3D conversions in general.
* WhatCouldHaveBeen: Matthew Belamy was writing the score, but had to abandon midway through as Music/{{Muse}} started a tour.
** [[http://www.youtube.com/watch?v=O1pW_71h3rk The original ending]] is closer to the original myth and movie.
*** Perseus slapping Zeus with a fish would've been closer to the original myth than the release ending.
*** The original cut of the film was closer to the original film, and with far less plot holes regarding Zeus and the Gods. A large portion of it, including the original ending posted above, is available as deleted scenes. The intended plot can be read here: http://www.chud.com/23299/by-zeus-the-version-of-clash-of-the-titans-you-didnt-see/
** The original idea for the movie was a CrossoverCosmology with [[MesopotamianMythology Tiamat]] waging war against the Greek pantheon and Perseus being assisted by [[EgyptianMythology Thoth, Osiris]], [[MesopotamianMythology Marduk]] and [[Literature/TheBible Yahweh]]. He would also apparently have a romantic affair with some "Cthonian Earth goddess." (The filmmakers apparently have something against Andromeda for some reason...)

!!Wrath of the Titans

* ActorAllusion: Not only does Hephasteus sound a bit like [[PiratesOfTheCaribbean Davy Jones]], but has the scraggly beard from human!Jones and even says "release the kraken" at one point (in reference to the first film).
** At the end, Zeus is basically using [[ThePhantomMenace the Force]] on the Makhai [[spoiler:and Force Lightning against Kronos!]]
* TheOtherDarrin: Rosamund Pike replaces Alexa Davalos as Andromeda.