sequel(s)
IS2
Cooper lands on Edmunds planet and is reunited with Brand. only to discover the planet isn't as uninhabited as it first appears...(more like Last Days on Mars but with a 200m budget im thinking a dead zombie Edmunds steals the embryos and makes an army of space zombies)
IS3
continuing from the cliff-hanger end of part 2 Coop and Brand escape Edmunds zombie planet only to encounter themselves and the original Endurance mission. They quickly realise the reason it succeeded was they had help from their older selves... (IS3 would be like BTTF2 revisiting the original movie due to time travel (turns out Coop and Brand are the 5th dimensional beings)
IS4
Coop goes back to earth only to find its the dawn of Mankind (TARS becomes the monolith)