The big show opened up with an extended "Previously on..." recap, and deservedly so. Last week's double-dose was truly amazing -- the sort of rollercoaster ride that has you clutching a pillow one minute and reaching for some tissues the next. I haven't yet quite forgiven the producers for offing sweet (or "thweet") Edgar -- heck, I'm still smarting from Sherry Palmer's bullet-ridden demise in season three -- but in the world of 24, an untimely death is almost like the greatest tribute a character can have. And so Edgar joins the legends of Bauer Land. May he rest in peace, preferably with a box of Krispy Kremes by his side.

Anyway, we knew there'd be some shenanigans this week when Vice President Hal (a.k.a. the same bastard who killed Laura Palmer) received his own title card in the opening recap. With Walt Cummings also dead and gone, the Prez needed some new, evil influence on his decisions, and when all else fails, why not cart in the hawkish Veep? It worked in season two, right?

Nevertheless, this episode was not about Hal and his sudden rise to relevance. It was about CTU. Basically, nerve gas had been released in the building, and the only safe zones were the Situation Room, the medical clinic (which, by the way, has NEVER been a safe place for anyone), Bill Buchanan's office, and, randomly enough, holding room 4 -- conveniently the location of our favorite hobbit, Lynn McGill. In case you forgot all this, don't worry. A random guy on a loudspeaker boomed through building and informed everyone about the situation. I half expected to hear him cough up a lung and die right there over the PA system, but apparently, his little broadcasting booth was the fifth, unmentioned safe zone. By the way, let's give a little round of applause to the first ever use of the CTU PA system. The building's seen a lot of chaos and tough times, and never has it been put to use -- not even during last week's Code 6 Evacuation. But tonight, they finally decided to break it in. Too bad that little safe zone announcement came after everyone had died.

Anyway, as Chloe all but curled up in a fetal position in the corner, Bill Buchanan (who was trapped up in his office) announced that he could still coordinate with Division. Cool! But what about gas masks? Do we have any of those? Well, the good news was that there were gas masks for everyone. The bad news: they were in the contaminated areas. Doh! Hey, I know this sounds crazy, but maybe next time, they should put the masks inside the safe zones.