The basic story line of Alcatraz is pretty simple: these used to be this high-security prison on an island off the coast of San Francisco. This was, of course, way back in the 1960s and such. Only the worst of criminals ended up there. Eventually the prison was shutdown and all prisoners were transferred - except that that's not what happened. Somehow, in a style similar to LOST, all the people that used to be in that mysterious island were teleported through time (but not space), and now, in 2012, San Francisco homicide detective Rebecca Madsen (Sarah Jones) goes around with Hugo - who is now a PhD in both Criminal Justice and Civil War History, and who goes by the name of Doctor Diego Soto (Jorge Garcia) trying to find all the former prisoners that used to be in the island.
The prisoners are slowly showing up in 2012 for an unknown reason - and in an unexplained fashion. They haven't aged at all, but their old evil intentions are still with them.
To put it simply - this show is awesome! Definitely worth watching.