Gray and Gray Morality: All of them are generally mild-mannered and approach their job with a commendable level of professionalism (given that their job is mentally dangerous to them as well), but that job does involve searching through people's minds in order to steal important secrets and (in the film's main case) using lies to give someone an idea from the inside.
Death Glare: Gives off a rather impressive one once they woken up in the plane to Saito. Seconds later, Saito was off using his connections to get Cobb back home.
Determinator: Deconstructed, he explores the concept of dream levels to the point he can no longer tell what is reality. The final scene where he finally sees his children, he doesn't even check to see if he's in a dream.
Disappeared Dad: Although he's not this through his own fault (most definitely not through his intention).
Loving a Shadow: The projection of Mal and the memories he relives in his dreams is the only connection Cobb still has with his dead wife. In the end, Cobb is able to admit Mal's projection is a poor attempt to hold onto his dead wife because his imagination can't come close to replicating the real Mal.
Manipulative Bastard: Several cases. Like not warning his team about being killed and sent to limbo. The Mr. Charles ploy. He also performed inception on Mal by destroying her belief in reality so they could wake up from their time in limbo.
Meaningful Name: "Cobb" means "dream" in Sanskrit, Hindi, Urdu, and Punjabi. It's also an old English word for "spider" (hence the word "cobweb"). Fitting, for a man who weaves webs and traps others in them.
Older than They Look: In the middle of the film, he has lived eighty years mentally—by the end, it's unknown how old he is.
A dream within a dream within a dream? Is that even possible?
Badass Bookworm: His job with the group is to do the research, and his hallway fight definitely pushes him into badass territory.
Butt Monkey: Poor Arthur. He gets shot twice at the beginning. Once just to cause him pain, and once BY HIS OWN TEAMMATE (admittedly to wake him up). When it comes to testing out the "kicks", somehow Arthur's always the one getting his chair knocked over, his gun dissed by Eames, and so on. His awesomeness at the end makes up for it, though.
The Comically Serious: Arthur is the most level-headed and serious member of the team, and as such is not amused by Eames' somewhat careless behavior, getting his chair constantly tipped over, or loud music.
Critical Research Failure: In-universe example, Arthur fails to find out that Fisher has had mental training to protect his subconscious from infiltration - arguably the most important piece of information needed when planning to infiltrate someone's dream.
Consummate Professional: He has an intense professionalism and intolerance to the lack of detail that goes into the inception job.
Karma Houdini: Double Subverted, it looks like he's going to be trapped in limbo but Cobb rescues him and he suffers no consequnces in having a business competitor inceptioned.
The Load: Plays the part for a good deal of the movie, being in a state of near death, but...
Older than They Look: He's the old man in the Japanese pagoda who shows up in the film's beginning and end.
Reasonable Authority Figure: While most shady CEOs would simply brush off Cobb's demands for the particulars of the inception on a "need to know basis", Saito actually answers questions if he's convinced they're good ones, and makes a personal effort to help facilitate the heist and "protect his investments".
Corrupt the Cutie: Professor Miles even refers to Cobb as wanting to "corrupt" one of his best students. Cobb openly tells her the job is not legal, but he, Arthur, and Ariadne herself each admit that after tasting the power of dream architecture, she would never want to go back. She willingly joins The Team.
The Heart: Her status as this helps her to get closer to Dom and realize that he has issues that need resolving.
I Just Want to Be Special: This is essentially what the dream world offers compared to reality and is what Cobb counts on for Ariadne to join the team.
Took a Level in Badass: The mission was called a failure when Fisher was sent to limbo but she devised the plan to go find him and pull off the mission, Eames and Cobb didn't pick the extra limbo time but she's a fast learner. She also shoots Mal.
The Watson: Well how else would anyone watching the movie know what's going on?
Reality Warper: Only in the dream world, Eames is the "forger" in the team which may explains why he is the most competent member in the team during the execution of the mission. His forging ability allows him to pull out a grenade launcher out of nowhere in the first level, shapeshift in the second level and to a certain extent become a One-Man Army in the third level.
Warrior Therapist: He works out most of Fisher's "problems" before and during the dream. He even sarcastically mentions that he should be getting paid more by Fisher than Saito for the job.
Why Do You Keep Changing Jobs??: He's somehow able to get a job placement in the Fisher company right within their head office to observe Browning. His justification? "References are sort of my specialty."
Yusuf (Dileep Rao)
Do you still dream, Mr. Cobb?
Badass Driver: In the first layer, he has to continue driving the van and perform the kick while the projections are trying to kill them.
Bollywood Nerd: A cool nerd, though, and one who can handle himself in the heat of action, which is key considering his dream is the top layer.
I'll tell you a riddle. You're waiting for a train, a train that will take you far away. You know where you hope this train will take you, but you don't know for sure. But it doesn't matter. How can it not matter to you where that train will take you?
Anti-Villain: The projection of Mal only wants to have Cobb all to herself but sabotages every dream mission he does.
Ax-Crazy: She's a dangerous lunatic who kills several people to get to Cobb.
Big Bad: She's the main antagonist of the film who tries to sabotage all the dream jobs. This is eventually revealed to be much more complicated as she's an aspect of Cobb's guiltridden psyche, so he's essentially fighting his own angst.
Brainwashed and Crazy: Cobb perfermed inception on the real Mal so she could escape limbo but she ended up unable to tell dream from reality and wanted to kill herself to keep waking up.
Brainy Brunette: Before her breakdown, Mal was the one who originally came up with the idea of totems, items that would stabilize a dreamer's sense of reality. Oh, the irony.
Broken Bird: The real after waking up from limbo stopped believing in reality.
Dissonant Serenity: When the dream is collapsing and everyone else is running around frantically, what does Mal do? She calmly walks through the destruction and is amused at how Dom gave Saito the wrong documents.
Dream Apocalypse: Cobb eventually comes to terms with the fact that Mal is just a projection of his dead wife, which is simply not good enough. Mal flies into a rage in response and Cobb is forced to kill her, where she cries that she doesn't want to die but remain with him.
Implacable Woman: Absolutely relentless and nearly impossible to reason with. Even if you're a trained dream infiltrator, when she shows up it's time to panic.
The Lost Lenore: To Cobb, who is still heartbroken after losing her to a suicide which he personally witnessed.
Love Makes You Crazy: Her love for Cobb and her children drove her to frame him for murder so they could be together in the "real world", which she was convinced was one more layer above what Cobb thinks is the real one already. The Mal projection simply wants Cobb and her to be together forever and is willing to kill for it.
Missing Mom: Her kids don't even understand why she is gone.
Thanatos Gambit: Mal commits suicide, but makes it look like Cobb murdered her so he'll be compelled to do it with her or lose custody of the children. Of course, like the many characters who kill themselves in dreams in this movie, she doesn't believe she's really dying.
Tragic Villain: Mal really has no choice about being a psychotic, murderous, obsessed Femme Fatale. She just wants to be with Cobb forever, but the villainous Mal in Cobb's dreams isn't even his real wife, but a shade of the woman he can't bear to forget. The dead Mal herself was brainwashed by Cobb, but inadvertently became so obsessed with the notion of her world not being real that she killed herself and framed Cobb for it. All out of love.
Walking Spoiler: The trailers make it out that she's the Psycho Party Member of sorts, but given the spoilers, she's actually Cobb's wife who killed herself and continued to exist through Cobb's guilt, manifesting into something... unstoppable.
At the end, he called me to his deathbed. He could barely speak; but he took the trouble to tell me one last thing. He pulled me close... and I could only make out... one word: "Disappointed."
Meaningful Name: Fischer's name may be a reference to the Arthurian legend of the Fisher King, whose kingdom physically changes to parallel his wounds and suffering; this is appropriate given that much of the film takes place within his troubled mental landscape. Also, "Robert Fischer" was the name of the famous chess player.