Saltwater Pool/lightning Scenario for computer game

[mkultra]

TL;DR Summary: What would happen if a bolt of continuous lightning hit an enclosed saltwater space with someone swimming far below the surface?

Hello! I'm actually asking this as a DM for a DnD campaign. One of my players trapped a bad guy within a large (30m/side) freestanding cube of saltwater. This cube was then struck by a continuous bolt of lightning at one end. Would the electricity flow around the surface of the cube, leaving the swimmer largely unharmed, or would the current course through the cube and fry him? Thank you so much!!!

 

[Baluncore]

Welcome to PF.
The underwater swimmer will be safe, but only while they remain beyond a few metres from the point of the strike. If they then rise out of the surface, the strike may transfer to them, and kill them. If they do not come to the surface, they will drown.

 

[Vanadium 50]

Is magic lightning even electricity? It seems not to burn wizardly fingertips.

And what about charge conservation?
"Wizard, are you sure you got him?"
"I'm positive"