On the fifth anniversary of the Mikaelson's defeat, Marcel is king of the city and welcomes the unsired vampires to New Orleans, only to find they pose an unexpected threat to his rule, leading him to seek counsel from an unlikely source.

After being cured and woken, the Mikaelson siblings join Hayley in an effort to rescue Klaus from captivity, even if they must face Marcel in the process.

After five long years apart, Klaus attempts to reconnect with his daughter, Hope. Elijah mediates a conflict between Hayley and Freya to determine the best way to protect the family.

While Klaus remains behind with Hope, Elijah and a reluctant Vincent join the hunt, which puts them on a dangerous collision course with an unlikely new threat.

After being marked by The Hollow's dark magic, Klaus and Marcel experience the symptoms of a malevolent haunting. Meanwhile, Hayley and Elijah head out to speak with Mary.

When it's discovered that The Hollow has employed a mysterious servant to do its bidding, Klaus and Elijah host an elaborate party in order to lure the new threat out and uncover its identity.

When it's discovered that The Hollow's latest servant is on the loose, Freya places a protection spell on the compound, forcing Klaus, Hayley and Hope to remain inside. Meanwhile Elijah takes matters into his own hands.

Old wounds are re-opened when Elijah and Marcel are forced into an uneasy alliance. Together, they meet with Alaric who has tracked down a crucial artifact that could help in their fight against The Hollow.

When The Hollow sends a terrifying message to Vincent, he must team with Hayley and Freya to embark on a desperate mission to stop the Hollow once and for all - even if it requires a heartbreaking sacrifice.

Rebekah and Kol return home to stand by their family against the Hollow. Freya recruits Hayley for a dangerous journey. Marcel leads a hunt for the Hollow. Kol considers the lengths he'd go to see Davina again.

When it's discovered that The Hollow is using a magical totem to fuel her power, Freya enlists Rebekah and Klaus' help to locate and destroy it.

When The Hollow targets the most vulnerable Mikaelson, Klaus is forced to rely on Vincent, who believes he can use The Hollow's own dark magic to defeat their enemy for good.

The Mikaelsons find themselves out of options as they face the all-powerful and un-killable entity known as The Hollow. With the life of Hope at stake, Vincent proposes a final, desperate plan.