The plan had several parts:
- Send the Endurance through the wormhole to find humanity a new home
- Construct massive space stations on the ground capable of holding most or all of Earth's current population
- Use Professor Brand's solution for gravity to launch the stations off the Earth
- Relocate humanity onto a new habitable planet
Unbeknownst to NASA and the crew of the Endurance, Professor Brand never intended Plan A to be a viable option. He used Plan A as a means to motivate funding to NASA and to eventually leave the Endurance crew with no choice other than to implement Plan B. Professor Brand considered Plan A to be impossible because in order to solve his gravity equation, he would need unobtainable data from the Singularity of a black hole. Professor Brand went to great efforts to conceal this fact from everybody, including his daughter Amelia and Murph. For years he pretended to be attempting to solve the gravity equation with Murph, despite the fact he had previously determined it was unsolvable before the Lazarus Mission left Earth, ten years before the Endurance.
On his deathbed, Professor Brand finally admitted to Murph that Plan A was a ruse. This prompted Murph to send a message to her father, accusing him of being aware of the lie and abandoning her to die on Earth. This proved to be a revelation to the entire Endurance crew, but not to Dr. Mann.
Later on, Cooper and TARS sacrifice themselves to allow Dr. Brand to begin Plan B on Edmunds' planet. TARS was tasked to enter Gargantua, glimpse the singularity, and relay the data back to Earth, giving humanity a chance to initiate Plan A. TARS was ultimately unable to transmit to Earth due to the black hole's immense gravity. However, Cooper and TARS entered the Tesseract and were able to relay the quantum data to Murph using the watch Cooper gave to Murph before leaving Earth. Plan A is implied to be successful as Murph's completion of Brand's gravity equation allowed the launch of very large space stations to depart from Earth, one being Cooper Station, named after Murph, not her father.