Quick recap
Ulmo, lord of the waters, sends the man Tuor to Gondolin, the hidden city of the Elf-king Turgon, with a warning: it won't last. Turgon doesn't listen. Tuor stays, marries the king's daughter, Idril, and they have a son, Eärendil. Maeglin, Turgon's nephew, wants Idril and gives Morgoth the way into the city. The assault comes with dragons and Balrogs. Ecthelion kills Gothmog, lord of the Balrogs, and dies with him. Turgon dies in his own tower. Tuor and Idril escape with the boy through a secret tunnel, and Glorfindel falls fighting a Balrog to save the group. Christopher Tolkien shows how the tale changed since 1917.

