Mark and Helly as Orpheus and Eurydice

I'm sorry if this has been posted before!

Although many people attach the myth to Mark and Gemma, there's foreshadowing for it being Mark and Helly (1x01).

Quick summary: In Greek mythology, Orpheus descends to the Underworld to reclaim his dead wife, Eurydice, he meets Hades who tells him that he can take Eurydice with him if he doesn't turn to look at her as she follows behind him out of the Underworld. Orpheus ends up losing her again after looking back at her prematurely during their ascent.

I think Gemma will make it out alive. It'd be too tragic and too easy to simply kill Gemma off. What's the point of writing an entire episode focused on her being alive and suffering just to kill her off?

So, I think Helly might be the one stuck down there/sacrificed. It'd also be tragic, but Helly lives on borrowed time (very little) and unlike Gemma, Helly/Helena hasn't experienced 'death' yet (like Eurydice).