The Christmas cliffhanger started innocently enough as surgeon Boyd Rolleston prepared to wed flirty doctor Harper Whitley.
But celebrations turned to turmoil when disgruntled Gareth Hutchison returned to Shortland Street hospital in order to exact his revenge on Dr Drew McCaskill.
When the shooting becomes a hostage situation Murray Cooper's father Len is shot and killed.
Drew is presumed dead after being hit once by a bullet fired by Gareth and again when a mystery shooter appears, wielding the same weapon.
Writers leave the audience to decide whether it was his disgruntled ex-wife Gin, Margaret whom he discovered to be pocketing money, or fellow doctor Victoria, who he squabbled with over a bad reference.
A picture previously released to the Herald on Sunday showed a distraught Harper with her wedding dress covered in blood - but tonight's "red wedding" gave no explanation for the stained white gown.
Producer Simon Bennett said the finale was the "biggest cliffhanger" he has worked on in 20 years.
Accompanying the action, were award-winning opera trio Sol3 Mio singing the classic Santa Lucia in a cameo scene where Dayna and George use the cancelled wedding to tie the knot themselves.
The pair seemed completely oblivious to the drama unfolding at Shortland Street.
A montage of slow motion movements put half of the cast in Gareth's firing line, after Vinnie and Mo gallantly jump to their feet to save the day and a bullet is fired.
The show returns to Kiwi screens on January 18 next year.
-nzherald