What Is The Mortal Cup On 'Shadowhunters'? This Ancient Artifact Has An Important 'Mortal Instruments' History

Freeform (formerly ABC Family) is debuting a new action-packed supernatural series in the form of Shadowhunters on Tuesday night.For those who don't know — and didn't tear through the books with an obsessive determination like I did — Shadowhunters is based on the YA series The Mortal Instruments by Cassandra Clare and follows a race of part-angel, part-human demon hunters. The first episode is titled "The Mortal Cup," but what is the Mortal Cup in Shadowhunters lore? It makes sense this phrase is the title of the series premiere, because it will undoubtedly play a big role throughout the season.

According to the episode synopsis, "The Mortal Cup" will introduce Clary Fray, who has lived a normal life as far as she knows, until everything begins to change on her 18th birthday when her mother is kidnapped. Thrown into the world of Nephilim (the human-angel hybrid demon hunters), also known as Shadowhunters, Clary meets some of these warriors — as well as other supernatural creatures like vampires and warlocks — and begins to see more of an entire world she never knewexisted. But the biggest thing Clary learns is that she herself is a Shadowhunter, and to save her mother she'll have to unlock her past.

So you're probably wondering: What exactly is the Mortal Cup and how does it figure into Shadowhunters? Well, in the book series, the Mortal Cup is one of the titular Mortal Instruments (makes sense, right?), which include three divine items given to the first Shadowhunter by an angel named Raziel. The other two instruments are the Mortal Sword, which compels Shadowhunters to tell the truth, and the Mortal Mirror, a portal to the Nephilim's home country. The Mortal Cup, however, is the instrument used to create Shadowhunters. If a mundane (their word for regular humans, like Harry Potter's "muggle") drinks from the Cup, they can become a Nephilim — though not everyone who drinks does — so it's incredibly important.

All that make sense? Good, now let's talk about what this means for Shadowhunters, the TV series. In the first book of Clare's series, City of Bones, the Mortal Cup has been lost by the Nephilim and Clary is the only person who knows where it is. But, there's a catch: she doesn't remember where it is because her mother hid it, told Clary where it was, and then wiped her daughter's memories. The first book largely follow's Clary's mission to find the Cup as a way of rescuing her mother from the kidnappers. If Shadowhunters follows this story, which based on the pilot it seems to be doing, the Mortal Cup is going to play a big part in Shadowhunters' first season.

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