What is Azrael’s Blade and when did it first appear in Lucifer?

The flaming sword hasn't been seen since season two, making its return in the latest batch of episodes a major surprise, but some viewers may have forgotten exactly why the item is such a big deal.

Never fear: RadioTimes.com has your essential refresher on Azrael's Blade, where we've seen it so far and why it's such a big threat to Lucifer and his allies. If you're looking for a more general overview of the series, read our Lucifer review.

What is Azrael's Blade? Mythology explained

The flaming sword is a divine weapon comprised of three distinct pieces, one of which is Azrael's Blade, which was once wielded by the angel of death and used to protect the Garden of Eden.

The ancient item is feared by the celestial community as it is capable of eradication i.e. if you are killed with Azrael's Blade, you go to neither heaven nor hell, but are simply wiped from existence altogether.

It was God who chose to split the flaming sword into three pieces – Azrael's Blade, the Medallion of Life and Amenadiel's necklace – as he felt this would make Lucifer less likely to use it against him.

When did Azrael's Blade first appear in Lucifer?

Azrael's Blade first appeared in the second season of Lucifer, when it was brought to Earth by Uriel (one of Lucifer's angelic siblings), who intended to use it to kill their mother.

Lucifer ended up having to kill Uriel with the blade in order to stop him, an act that left him racked with guilt and briefly trapped him in a hell loop.

He keeps the blade in his possession and is initially doubtful when his mother tells him it is one component of the flaming sword, but her claim is proven when Lucifer's anger causes it to come alight.

He soon tracks down the other two pieces, one of which is discovered by a human named Earl Johnson and the other is found to be the necklace Amenadiel has been wearing for millennia.

Lucifer's mother, the Goddess, wants the flaming sword so that she can return to heaven and wage a war against her estranged husband, God himself.

However, her son realises that this would inevitably cause bloodshed and wishes to find a more peaceful solution, using the sword to cut a hole into an alternate and empty universe.

He convinces Goddess to move to this parallel reality as it offers a blank slate for her to create a universe in her own image, and she reluctantly agrees.

Before closing the rift, Lucifer throws Azrael's Blade and the Medallion of Life into the other universe, removing the necklace to return it to Amenadiel – thus diminishing the threat of the weapon seemingly forever.

In a later episode, Amenadiel forges a mentor relationship with a troubled teenager named Caleb and when the boy is killed, he gives him his necklace to be buried with.

How did Azrael's Blade return in season 5?

Azrael's Blade returns in Lucifer season five part two due to the devious scheming of Lucifer's twin brother, Michael Demiurgos.

He sends the Angel Gabriel into his mother's universe to retrieve Azrael's Blade and the Medallion of Life, a feat that requires great strength and could not be achieved by just anyone.

He then digs up Caleb's grave to retrieve Amenadiel's necklace and complete the weapon, which he intends to use to strengthen his claim to becoming the next God, following their father's retirement.

Read more:

• Lucifer musical episode songs ranked: who's really singing?
• Lucifer season 5 part 2 ending explained: Who becomes the new God?

Lucifer season 5 part 2 is available to stream on Netflix. Looking for something else to watch? Check out our guide to the best series on Netflix or the best movies on Netflix.

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