Adric, Katarina, Sara Kingdom and Rory Williams. Also a robot companion named Kamelion was destroyed as well. Adric was the only longstanding companion to die in the TV series. In the TV movie Grace Holloway dies, but is brought back to life. In the revived series Captain Jack Harkness is killed in Parting of the Ways, but is brought back to life by the Bad Wolf, rendering him immortal. Donna Noble is said to have "died" in "Journey's End" because of her memories of the Doctor being erased, but she's technically not dead. Three individuals have died after accepting invitations from the Doctor to become companions: Astrid Peth ("Voyage of the Damned"), Jenny (the Doctor's Daughter -- however she partially regenerates and comes back to life, though the Doctor believes her to be dead), and "Lynda with a Y", a young woman featured in the "Bad Wolf"/"Parting of the Ways" two-parter. There have also been companion deaths in the novels and comic strips, but these aren't being included here.