ok, so my GF was driving her 2008 accent 5 days ago. she turned onto a side street and it just died.. and would not start back up. did'nt overheat, wasnt skipping or anything prior. we had it towed home. I did a compression check yesterday. CYL 1, 50psi CYL 2, 0psi CYL 3, 0psi CYL 4 45 psi.. What the heck happend? any ideas?

 

Sounds like the timing belt let go.
Because it is an "Interference" engine , there is a good possibility there are some bent valves. An exchange head assy and new belt should take care of it.
Gonna cost some to have the repair done, so expect it.