Can you remember how it all ended? ...

With finale season underway, we're taking a look back at some of television's best show-stopping moments.

Can you remember Hunnicut's final message to Hawkeye on 'M*A*S*H'? Or what happened to the 'Seinfeld' gang?

Test your knowledge with our end-all series finale quiz.

• CBS has March Madness all night.
• TV Land has an Andy Griffith Show marathon all night.
• At 8, NBC reruns the ER finale, if you missed it.
• TCM has Take the Money and Run at 8.
• At 9, FOX has a new America's Most Wanted.
• Lifetime has the movie Nora Roberts' High Noon at 9.
• Hallmark has the movie Love Takes Wing at 9.
• Also at 9: FUSE has the Rock and Roll Hall of Fame Induction Ceremony.
• At 10, History Channel has a new Ax Men.
• At 11:30, NBC has a new Saturday Night Live, with Seth Rogen.
• At 1AM, Cartoon Network has a new Bleach.

Check your local TV listings for more.

No, George Clooney did not show up for the series finale of ER.

But it was a pretty good finale anyway. It's impossible to please all fans of a long-running show in a series finale because we expect too much, and what we expect can change depending on whether you've been watching it since the beginning or just started four years ago. Do they focus on the old cast members coming back and focus on the people who have been there for the past few years? Do they tie up all loose ends neatly in a bow or leave things open-ended because that's how life is? ER managed to do both last night.

After the jump, the good and bad about the last episode of ER.

As we bid farewell to ER tonight, I can't let it pass without commenting on my all-time favorite episode of the series, the incomparable "Love's Labor Lost". Anyone who's a fan of the show should remember the heartbreaking story of a young couple, Sean and Jodi O'Brien, who were about to give birth to their first child and the ultimate devastating ending.

It was a gut wrenching, too-painful-to-watch hour of television that I've never forgotten. While there are many other brilliant episodes in the show's history, this stands out as one of the first examples of how powerful ER could be.

• At 8, NBC has an ER Retrospective, followed by the ER series finale.
• CBS has a new Survivor at 8, then new episodes of CSI and Eleventh Hour.
• ABC has a new In The Motherhood, followed by a new Samantha Who?
• FOX has new episodes of Bones and Hell's Kitchen.
• There's a new Smallville on The CW at 8, then a new Supernatural.
• AMC has It's A Mad, Mad, Mad, Mad World at 8.
• Discovery has two new episodes of Destroyed In Seconds at 8, then a new Treasure Quest.
• Also at 8: Nickelodeon has a new Penguins of Madagascar.
• At 9, Spike has a new TNA Wrestling.
• At 10, Food Network has a new Ace of Cakes.
• The Biography Channel has a new Chris Isaak Show at 10.

Check your local TV listings for more.

After the jump, the late night talk shows.

Yup, tonight is the final ER. NBC will have an hour-long retrospective at 8 PM and then the two-hour season finale of the show at 9 PM (sorry, fans of My Name Is Earl, The Office, and 30 Rock). We've seen several old favorites come back this season in previous episodes, and we know that a couple more are coming back for tonight's last hurrah. Will George Clooney be one of them?

Clooney already made an appearance on the show with Juliana Margulies a few weeks ago, and I liked the episode enough. It's just that there was a slight something missing from the episode, something concerning Doug and Carol and them not knowing that the kidney going to County General was for Carter.

Time to pull the plug.

After 15 seasons, 'ER' calls a code blue for the last time in its series finale tonight (Thu., April 2, 9PM ET on NBC).

Over its run, the show racked up 123 Emmy nominations (the most in TV history), engaged millions of viewers and made stars (ever heard of a guy named George Clooney?). Doctors and patients came and went, lives were saved and lost and hearts healed and broken.

As County General closes its doors for good, here's a look back at our favorite 'ER' episodes and memorable moments.

'ER'
(9PM, NBC) series finale
The Emmy, Golden Globe and Peabody-winning series closes out its 15-season run with an appropriate send-off that will give fans updates on their favorite characters.

More 'ER' friends – Eriq LaSalle, Alex Kingston, Sherry Stringfield, Laura Innes and Thandie Newton – return to the hospital tonight to support John Carter (Noah Wyle) as he opens his new medical center.

Meanwhile, the new crew gets some final screen time, too, as John Stamos' Gates treats a teen whose boozy games have led to alcohol poisoning, and Carter helps a new intern (Alexis Bledel) whose pregnant patient is about to deliver twins. Hmmm, a 'Gilmore Girl' in the ER? Sounds like spin-off potential to us ...

So this Thursday at 9pm, the series finale of ER airs on NBC. I think that even former fans who drifted away from the show when Anthony Edwards was killed off, or when Noah Wyle left, or when they just didn't enjoy the show anymore because it had been on for too long will tune into the finale. You can't watch a show for so many years and then just forget all about the finale. The thing has been on since Bill Clinton's first term, so we gotta find out how it ends.

The episode (like this season in general) will also have some familiar faces coming back to County General, and probably some in pictures and/or flashbacks (the episode will be preceded by a retrospective at 8pm). After the jump, a video sneak peek at the episode (and, yes, there are possible spoilers, so proceed with caution!)

• CBS has March Madness all night.
• Sci-Fi has a Star Trek: Enterprise marathon all night.
• At 8, ABC has the series premiere of In The Motherhood, then new episodes of Samantha Who?, Grey's Anatomy, and Private Practice.
• NBC has a new My Name Is Earl at 8.
• FOX has new episodes of American Idol and Hell's Kitchen.
• The CW has a new Smallville at 8, followed by a new Supernatural.
• At 9, NBC has a new Office, then new episodes of 30 Rock and ER.
• There's a new TNA Impact on Spike at 9.
• At 10, A&E has a new episode of The Beast.
• Food Network has a new Ace of Cakes at 10.
• Discovery has a new Treasure Quest at 10.

Check your local TV listings for more.

After the jump, the late night talk shows.

After 15 years, the lights will be turned off at County General.

The groundbreaking, seminal series 'ER' comes to an end April 2, and before saying goodbye, fans sounded off about the show's memorable doctors and moments.

Did you see "The Wall" last night on ER?

I don't know if this so-called "legendary" wall has ever been mentioned on the show before (if it has, I apologize), but I thought it was a rather out of the blue piece of symbolism for the show to have in its final episodes. Neela said that she had heard rumors about the wall but wasn't sure if they were true or just a myth, which I don't really understand because we're talking about a wall in a lower floor room with name tags on it, not the mythical land of Narnia.

All the big names were there from the quick shots I could see: Greene, Ross, Lewis, Gallant, Lockhart, Pratt. Was Carter's tag up there or did he take it off the wall when he came back this season?

• CBS has College Basketball all night.
• At 8, ABC has a new Ugly Betty, followed by new episodes of Grey's Anatomy and Private Practice.
• NBC has a new My Name Is Earl at 8.
• FOX has new episodes of Bones and Hell's Kitchen.
• The CW has a new Smallville at 8, then a new Supernatural.
• At 9, NBC has a new episode of The Office, followed by new episodes of 30 Rock and ER.
• Spike has a new TNA Impact at 9.
• ESPN has more coverage of the World Baseball Classic at 9.
• Also at 9: Hallmark has the movie The Nanny Express.
  
• At 10, A&E has a new episode of The Beast.
• Discovery has a new Treasure Quest at 10.
• There's a new Ace of Cakes on Food Network at 10.

Check your local TV listings for more.

After the jump, the late night talk shows.

How well do you know the show?

Since premiering in 1994, 'ER' has seen a lot of action -- and quite a few cast changes. George Clooney, Anthony Edwards, Julianna Margulies, John Stamos and many others have walked the halls of County General.

After 15 seasons of ups and downs, it's time to test your 'ER' knowledge by taking our quiz.

So yes, George Clooney was indeed on ER last night.

The episode, overall, was very good. The banter between Carter and Benton was great, and it was great to see Eriq LaSalle again, and the way they reintroduced Doug and Carol into the plot was really well done and didn't seem forced or stupid. The show deserves points for that. It didn't work 100% though. Here's what I loved and what I didn't love about the episode.