Mann, the leader of the Lazarus mission. However Mann's purpose in this film is to represent the worst of humanity - the clue is in the name - and it is soon revealed that Mann lied about his planet being habitable in order to return to Earth, and he then attempts to kill the Endurance crew and steal their spacecraft.
Dr. Mann's motive for attempting to kill Cooper in Interstellar was driven by his desperation and self-preservation. After arriving on his planet and realizing it was uninhabitable, Mann didn't want to die alone.
Mann is an example of humanity's selfish nature – his surname is a not-particularly-subtle bit of signposting – as he deliberately manipulates his data to pretend that his ammonia-filled planet is habitable. He sabotages Coop's crew purely to escape from the planet and make it back to Earth.
They awaken Mann from cryostasis, and he fills them with the hope that the planet he discovered could support human life. However, he privately reveals to Cooper that this is a lie. He falsified the data so that NASA would send a crew to rescue him.
Mann faked data about his planet's viability so Endurance would rescue him. Mann breaks Cooper's spacesuit visor and leaves him to die, and flees to Endurance on a shuttle; Romilly is killed by a bomb Mann set to protect his secret.
He intended to benefit from the Endurance's proximity to Gargantua to study the black hole and gather as much information as he could to help Dr. Brand with his equation. The immense time slippage from the Gargantua black hole causes 23 years, 4 months and 8 days to pass while Cooper and Brand are on Miller's.
Romilly further explains that wormholes function by "folding" space in half and allowing an object to travel from one side of the wormhole to the other instantaneously, representing this concept by bending a sheet of paper in half and pushing a pencil (representing the Endurance) through the paper.
However, when the prospects of humanity's survival on his icy planet became bleak, he was forced to face his own survival instincts. Driven by his selfishness and cowardice, Mann becomes the secondary antagonist of Interstellar.
How and why did Mann fake the data in Interstellar?
Mann finally went through with his survival intentions: to fake his planet's data from hypothetical models from his robot KIPP, booby trapping KIPP, and put it in a more optimal perspective, and to be a leader on humanity's new planet.
Set in a dystopian future where humanity is embroiled in a catastrophic blight and famine, the film follows a group of astronauts who travel through a wormhole near Saturn in search of a new home for humankind.
TARS relays the quantum data to Cooper in Morse code. Cooper in turn relays the quantum data to Murph, in Morse code, through the hands of a wrist watch. Murph somehow knows it's her father relaying quantum data to her through the watch.
Mann's last words are, 'Brand, I don't know what Cooper's told you, but I'm taking control of the Endurance, then we'll talk about continuing the mission. This is not my survival, or Cooper's - this is mankind's- '.
Mann was marooned on this planet for 35 years, as evidenced by the 23-year time dilation on Miller, the two-year trip to Saturn and the launch of the Lazarus missions which predated Endurance's launch by ten years.
Through Dr. Mann says, “I'm here for you,” while Cooper dies, Mann can't tolerate the suffering and turns off the speaker in his helmet. At this point, the film cuts to Murph turning her jeep into the family cornfield, where she will set fire to the corn in order to force Tom to leave.
Once Romilly and TARS were able to re-boot KIPP, the robot began to display the true nature of the planet - data that contradicted Dr. Mann's claims that he found a habitable surface. Sensing danger, TARS urgently orders Romilly to step back. KIPP's mainframe detonated killing Romilly and destroying Mann's compound.
Mann realizes his planet was uninhabitable. He dropped probes at nearby locations with the hope of finding a rocky, habitable surface, below the frozen clouds they stood on. After years of probing and exploration, he found no surface.
He ended up in the hospital bed because he went unconscious when the Tesseract was closing, and the 5th Dimensional beings transported him out of the black hole and assisted him through the Saturn wormhole. He was then found by rangers from cooper-station, and was taken into medical care.
Brand : Why didn't you sleep? Romilly : Oh, I had a couple of stretches. I stopped believing you were coming back. Something seemed wrong about dreaming my life away.
I think if he'd somehow made himself stay (through binary, etc), he would have altered the future and he would have disappeared into the blackhole forever, but the fact that he gave the co-ordinates of the NASA base and sent himself to space, he stayed in existence even though he does alter the...
Ok, now follow a few steps. Murph was 10 years old when Cooper left. Cooper traveled for 2 years to the wormhole and subsequently lost 23 years in gravitational time dilation on Miller's planet. When he returns to the Endurance he receives Murph's message that she is now the same age as Cooper when he departed.
After finding his planet's conditions to be promising for human life, Edmunds sent a "thumbs up" signal back to NASA on Earth. He subsequently settled into hypersleep and awaited to be rescued. During this time, a rockslide occurred and destroyed his landing pod, causing Edmunds' death.
Despite being a robot who follows the order of his crew, TARS is quite intelligent and is capable of acting on his own. Unlike his crewmate CASE he's much more of an extrovert and talkative. He suspected the possibility of Mann betraying the crew and disabled the auto-pilot to prevent Mann from stealing the Endurance.
What did Cooper tell Murph with the watch in Morse code?
Cooper gives Murph his watch. From inside the 'tesseract' of the fifth dimension Cooper sends a message using Morse code through the seconds hand of Murph's watch. It is the quantum data that will help humanity escape dying Earth. When she works out the formula, Murph shouts 'Eureka!
