Cillian Murphy did not receive an Oscar nomination, despite being nominated for a Golden Globe, for portraying Patrick/Patricia "Kitten" Braden in Breakfast on Pluto.
Cillian Murphy plays the naturally challenging role of a transgender character. This is a bit different than say an Eddie Redmayne in The Danish Girl though. The film's tone is more irreverent than self-satisfied, and the character is of a different nature. Patrick/Patricia, or just Kitten, is who Kitten is really from the first time we see the character as an adult. There is no "transformation" period in Murphy's performance, though that might partially stem from a far more intelligent acting choice, but in terms of the character there is no moment where Kitten undergoes any surgery for example. Kitten just starts out being Kitten, and that is that. This still offers a challenge nonetheless to Murphy, in fact it also guarantees that if part of his performance isn't working none of it really will. Murphy though is basically an actor who only takes on challenges. He's an actor who has perhaps been associated best in the mainstream in his creepy role as the Scarecrow in the Dark Knight trilogy, from 2005 as well, but looking through his filmography there is no trend in terms of the roles Murphy takes.
Murphy's performance is entirely out on a limb because of that as he must create a rather unique presence as Kitten. Again though he has the advantage from starting at this point as Kitten already exhibits feminine physical mannerisms. Now Murphy deserves a great deal of credit in this regard given that he seems far less natural at first when dressed in a schoolboy's attire, but when in Kitten begins to wear dresses suddenly everything about his performance seems as it should be. That's not a criticism against his initial portrayal when Patrick is school, rather Murphy so effectively realizes the idea of the character embracing exactly who they want to be. Murphy is equally impressive in his vocal work here as he manages as higher pitched voice for the character that never seems forced or unnatural for even a moment. This is a bit different than director Neil Jordan's previous foray into somewhat similair subject matter with The Crying Game that we know the biological gender of the character from the outset, hey even old Stephen Rea gets a heads up this time, but seeing his work here, Murphy might have been able to pull off Dill in that film as well.
This is not just some sort of technical accomplishment by Murphy though, but rather a springboard to realize Kitten past this distinguishing aspect to the character. Kitten technically speaking is not atypical just for that one element by any means, and Murphy realizes a most unique presence with his performance. Murphy brings this energy to his work that really is quite something to see from the man who one could see brood so effectively in his villainous turns. Kitten is about life though and Murphy realizes that with the sheer exuberance he brings to his performance. A running element in the film is the way that so many take a liking to Kitten, and not necessarily in a lustful way. Murphy is just rather wonderful in the part as he succeeds in making Kitten's energy just oh so very endearing. It isn't what one would always call subtle, but nor should it be. Murphy makes this convincing in that he's not in your face yet he's in no way quiet. What Murphy projects is this desire for a happiness, even when it is not even true at the time, that is so charming that it's hard to dislike Kitten.
The film isn't a great film by any means, in that it has a great central character, but it doesn't really know what to do with Kitten. The film kind of jumbles around from comedy to drama with the drama either coming from Kitten searching for biological mother, or dealing with social problems in Ireland itself. The film never quite balances the tone perfectly, in that kind of fails to build towards anything, but Murphy does balance the tone within his performance. Murphy's trick to this though is to merely keep Kitten consistent as a character, and everything that comes from Kitten is entirely genuine due to how effectively Murphy finds his character. Murphy is especially strong in the way he interacts with the rest of the cast, and is astute in playing against them in order to bring out what's best. This includes the directly comedic scenes involving Brendan Gleeson, or the semi-comedic ones involving Stephen Rea. Murphy always allows the humor to come naturally from Kitten eccentricities flowing together with the similarly eccentric men into some entertaining madness. On the more dramatic side there are the relationships with the local priest (Liam Neeson) where Kitten's connection is stronger than one would expect, or the eventual pseudo connection with Kitten's mother. In these scenes Murphy finds a real poignancy in revealing the tender desire in Kitten for a real acceptance, as Murphy so beautifully plays the vulnerabilities in Kitten when the reunion is attempted yet aborted. When there is finally someone who recognized Kitten as his own, Murphy makes it surprisingly heartwarming as he brings such joy in Kitten finding a place to be loved. The film never quite makes use of what Murphy fully. We get fits and starts of ideas, but the film does not articulate this into something special. Nevertheless Murphy's work standing out on its own is a remarkable accomplishment.