About:
San Fierro Underground is a classic GTA style storyline pack revolving around story of a small time thug and his close friend. The duo are forced to work against their will for local narc-dealer Julio Cruz. Dwelve into criminal underground and earn your freedom before the lunatic narcoboss decided to end you.

Introduction

San Fierro 1990. City of drugs,gang violence,cartels,mafia.Crime is all over the place. Thugs are using the situation to profit anyway they can. From small time pickpocketing to robbing entire bank convoys. Whole system is corrupt and city officials themselfs are using the situation to profit. Mayor force in city right now is Mexican drug lord Julio Cruz along with his corrupted officials that work for him. Cruz was dominating force in SF for few years and gained fortune smuggling. Right now new gangs are forming, each one trying to get a bite of the action. Local thugs Layne and Fred, who are friends since childhood are trying to profit robbing people on street. Their lives change after one unfortunate incident...

Check out the topic on GTA Forums : http://gtaforums.com/topic/759020-san-fierro-underground-storyline/

Storyline has been tested two times in its final version. I played it both times without crashing it worked fine. There are no gamebreaking bugs expect that in one mission car suddenly stops for no reason. I tried fixing it but It didn't work. To pass the mission just simply highjack the car and drive it to location.