I decided to start a thief/assassin character after getting my warrior to demigod levels of power and my first stop is the thieves guild in Riften. Everything goes according to plan: I clear some dungeons on the way, run away from some mammoths, the usual. Finally, I arrive at the city, I head on in(after telling the guard to bugger off) and make my way to the marketplace where I talk to Brynjolf. While discussing my lack of coin an arrow flies overhead, puzzled I break out of conversation with him and to my surprise Brynjolf charges off at a group of guards who have there weapons drawn, soon after Maven Blackbriar joins the fray along with several of the citizens. As more guards show up I'm left standing there wondering if there was an uprising going on or something. Eventually Brynjolf(almost single-handily) kills all of the guards an everyone goes about their business like nothing ever happened. Can anyone make sense of this? Was it just a glitch or has it happened to someone else?

Maybe the guards just saw him steal something and came at him with a vengeance...?

Sounds pretty hilarious if you ask me

I love when random things like this happen. Keeps the game interesting. I say roll with it, guards are annoying anyway...besides, if you're a thief, you want the local law out of the way anyway

Nice glitch, would be funny to see. Plus, free stuff

I stopped liking that place when they hustled me for an entrance fee.

Awesome. would love a vid of that fight XD
I had the typical glitch of everyone continues to stand around the plaza as if they were still watching his distraction. All of the shops are broken because of this.

No glitch!

This has happened to me twice, it usually happens when a guard catches a thief redhanded, if he runs into a building containing thieves guild members all hell breaks loose...it's awesome stuff!

Thats great, love events like that. The guards and thieves go at it regularly in Riften. Often when i amI am in town at night I see the guards and citizens killing a thief.

I watched 3 dragons attack Falkreath. They killed everyone except for 1 guard and myself.

Events like the OP and the one I experienced are what keeps the game fun and interesting. It adds a well-deserved amount of humor to a mostly serious game.

I can't comment on your experience - very odd - but something weird did happen to me in Riften yesterday. I handed in a quest to the Dunmer merchant in the market - finding out about his heritage - and he thanked me, gave me the reward etc. I then looked up, to see him confronting the female Orc merchant who asks you to gather Ice Wraith teeth (I think - can't remember if that's the right quest and can't remember her name, but she definitely wants you to gather something for her).

They exchanged a few angry words, before he pulled out a dagger and started stabbing her! She punched back a few times before pulling out her own dagger and joining in. I was very confused, even more so when other citizens started cheering them on and saying "my money's on the big one!" I'll admit I was egging the Dunmer on - he's a nice guy, from his quest - because it seemed like they were going to carry on till one was dead. Eventually the Dunmer did a mighty power attack and murderised the Orc lady. Then everything carried on as normal, everyone went back about their business.

I failed the Ice Wraith teeth quest...

I bet the guards were going after a thief. I see them all the time in Riften, and sometimes other cities, and the guards will attack them. Since Brynjolf is a thief he got involved on his side. It is really not uncommon, I am level 33 and have seen it probably 3 times at least.