Who will be sacrificed to take the Hollow down?
Fortunately, they brought back two old friends to help shepherd the details along.
The Hollows biography begins in 500 AD with a tribal celebration of a babys birth.

Credit: Bob Mahoney/The CW
Even Baby Hollow is scary.
The jaw bone is one.
Freya managed to track down the lineage of guardians who were entrusted with bones like the jaw bone.
Lo and behold, its Tyler Lockwoods pack.
The other bones must be in Mystic Falls.
And somehow, the Tunde blade is involved in this resurrection plan.
The good news is that Alaric trolls the old Lockwood Estate and finds a creepy ass ancient finger bone.
Plus, the Lockwoods kept records of the names of other families charged to guard the remains.
When Klaus is around, things tend to get a little murdery.
Klaus sends Elijah to recruit Marcel for a bro-themed road trip culminating in a meet-up with Ric.
Perhaps its time to mend bridges rather than throw people off of them.
Solid burn, Klaus.
Marcel has no idea hes been nominated to accompany Elijah.
Elijah explains there is an expert who has one of the bones and means to find the others.
They have a common goal.
Let bygones be bygones.
When Marcel balks at the word trust, Elijah produces the blade that can kill him.
Of course, Sofya hears the entire exchange.
Rookie mistake, E.
Over in the church, Klaus smells a witchy trap.
Hayley reminds him that the covens protect their own, which includes Hope.
Hes annoyed to see the Harvest Girls, fresh from their recent throat slittings, who have a deal.
The ancestors want to talk and they need blood to perform the spell.
Since Hope is a New Orleans witch, a combination of her father and mothers blood will do.
Klaus still smells a rat.
Theres something they arent telling him.
This is going to hurt!
The girls begin the spell.
Klaus and Hayley writhe in pain before landing in a shadowland of the other side.
Will they have to search purgatory for a helpful witch?
That would be a no.
Davina is there in all of her hooded glory.
Im happy to report her hair held up beautifully on the other side.
This is when things get a little sluggish.
Allow me to provide you the abbreviated version of the Hollows profile.
That resulted in Baby Hollow.
She hungered for power.
She liked to kill for fun.
At the word kill, Klaus perks up.
Davina stares him down.
You cant kill the Hollow.
Hes never met anything he couldnt kill.
Davina confesses that the Hollow does have a weakness.
She grabs Hayleys hand and witches her out of the shadowland.
Ric steps out of his car and fires an arrow at her heart.
She catches it, of course, and flings Ric down the road with a sweep of her hand.
Oddly, no blue orb vanished into the sky, or into Ric.
Sofyas body must be made of some special stuff to withstand that explosion.
Marcel and Elijah arrive just in time to find Ric limping along the street.
He describes the gorgeous vampire/witch combo who was looking for a particular creepy finger bone.
Marcel immediately realizes Sofya is the Hollows host.
He wants to save her.
Elijah wants to kill her.
To each his own.
Ric brings the argument to a halt by proving some information.
Elijah figures Sofya is halfway there.
(How would she know this information?)
Regardless, Marcel informs his bro that the cemetery was redeployed due to floods.
He knows where Del Robles is buried.
To the German sports car!
It all comes down to Hayleys bloodline.
Heres the short version: The tribes decided to kill the Hollow.
They tracked her with wolves, put a binding spell on her, and tied her to the ground.
The curse bound all those present to the full moon.
The Hollow created the werewolf curse.
She also has a crescent moon mark because her mother, the original werewolf, has the mark too.
The Hollow fears Hayley because Hayleys blood is her weakness.
That means Hopes blood is her weakness too.
Davina begs Hayley to trust her plan.
Hayley bolts out of the church.
Davina looks at the Harvest Girls and ominously says, You know what to do.
Remember when you though Davina was a good witch?
They get into an argument about who will be the keeper of the bone, but it doesnt matter.
Sofya is there to collect her femur.
All are surprised when nothing happens.
Davina totally forgot to tell Hayley that so that trap the Hollow, an immortal has to be sacrificed.
Sofya grabs the bone and leaves.
Davina will not hesitate to kill Klaus.
It doesnt take long for Klaus to figure this out either.
Davina fills in the blanks.
The Hollows bones wouldnt burn.
She haunts (blue orb), looking for the four bones that are separated.
Theres the jaw, the creepy finger, the femur, and a pelvis.
She wont stop until they are reunited.
Since that day is near, Davina wants to kill Klaus.
All she needs is Marcels blood, which is in that weird vine that can kill an original.
So thats what the Harvest Girls are doing!
She promises Klaus it will be painful, but she can make it easier.
Hope hears her father screaming, rips off her bracelet, and scurries out the window.
Meanwhile, Hayley and Marcel march into the church asking an invisible Davina to stop.
Oh, this is handy!
One death for the greater good!
Elijah barges in, offering his body instead, but Davina wont trade.
Davina magically takes Marcels venom, which slowly drips toward Klaus.
Suddenly, a voice shouts, I wont let you hurt us!
All turn to see Hope in the doorway.
She throws it DOWN!
Raise your hand if you want Hope to go up against the Hollow.
Later that night, Ric applauds Hope for her bravery.
Klaus all but rolls his eyes in Rics face.
Heres hoping Klaus at least makes a site visit so we can witness some sparks with Caroline!
Upstairs, Hayley gives Elijah the cold shoulder for offering to sacrifice himself in place of his brother.
Elijah shouts that Hope needs her father.
Hayley calmly says she needs him because she loves Elijah.
When Elijah arrives at Marcels house, the door is ajar.
He walks in, because hes an original who is afraid of nothing.
Its too bad the Hollow was there to stake him in the back.
Its also too bad the stake was covered in the death thorns.
If they kill off Elijah, Im boycotting this show.
I dont care if they werejust renewed for season 5.