Matt Murdock, Jessica Jones, Luke Cage and Danny Rand investigate criminals and fight injustice, unaware their paths are about to cross.

As a new conspiracy takes shape, Matt finds old habits are hard to break, Jessica gets in over her head, Luke tracks a lead, and Danny meets his match.

Elektra's secrets are revealed. Danny changes his tactics. Matt gives Jessica some legal advice. Luke searches for the White Hat.

Elektra's loyalties are questioned, Colleen clashes with an old acquaintance, and Luke proves he knows how to take a hit.

Matt, Jessica and Luke embark on a desperate search. Colleen and Claire debate heroism. Elektra tries to recruit an all-important ally.

As New York edges closer to disaster, Elektra sees what's beyond the wall, and the Defenders make a last-ditch effort to save the city.