The twist in the tale
When telling an anecdote, use the verb resultar (to turn out) to introduce unexpected outcomes. To deliver a plot twist, use the phrase resulta que (it turns out that). Because you are declaring what happened, this phrase is always followed by the indicative mood.
You can build up to the twist by setting the scene with words like curiosamente (curiously) or de golpe (all of a sudden).
Making matters worse
Sometimes, a twist just complicates things. To talk about a difficult or tangled situation, you can use the noun el enredo (the mess or mix-up).
If you unexpectedly bump into someone in the middle of this mess, use the verb toparse con (to run into). When things escalate and go from bad to worse, bridge your sentences with the expression para colmo (to top it off).
Reactions and wrapping up
When a turn of events leaves you scratching your head, you can describe the situation as desconcertante (baffling) or even inaudito (unheard of).
If the unexpected outcome was a letdown, use the expression llevarse un chasco (to get a disappointment or nasty surprise). Finally, when you want to wrap up your anecdote and summarize the chaotic sequence of events, you can start your conclusion with the conversational phrase total, que (long story short...).