Honestly, there's not one of Joe Kelly's 33 issues of Deadpool--plus the various annuals and specials--I wouldn't heartily recommend, but if you're looking for the creme de la creme and don't have hundreds of dollars to shell out to some dude over eBay like my buddy Jordan, here are the ones you really need to check out...
DEADPOOL #3 - "Stumped! Or...This Little Piggy Went...Hey! Where's The Piggy?!" I'm a sucker for any time 'Pool pines after Siryn, the fiery redhead then of X-Force (currently of X-Factor) whom he considered his one true love. Mark Waid first hooked them up in the second Deadpool mini, "The Circle Chase," then Kelly took the ball and ran with it. Deadpool spends so much time posturing and putting on his facade of ego and wisecracks, that it's always nice to see a different side of him, i.e. the one that turns into a nervous schoolboy whenever Siryn shows up. The nice thing is, while she doesn't totally reciprocate his feelings, Siryn does believe in Wade in a way nobody else does and there is something there. She wants him to be a better man, and at the end of the day, she's probably the only person he truly wants to be better for. Kelly understood how to play their interactions for laughs, but also how to really tug at the heartstrings, and this was his first shot to do so. The next two issues are also required reading, I guess, since they continue the story (and Deadpool fights the Hulk!).
DEADPOOL #11 - "With Great Power Comes Great Coincidence"
Not only my favorite issue of Deadpool, but probably the funniest single comic I have ever read. Kelly (with much assistance from editor Matt Idelson I have been told) came up with the brilliant idea to take an old Amazing Spider-Man comic and "Forrest Gump" Deadpool into the role of Peter Parker and Blind Al into Aunt May. Kelly doesn't just make up some generic Spidey story either, he uses an actual issue and changes nothing except the dialogue of "Peter" and "May" and their reactions to the ridiculously 70's shit going on around them. Al thinking Mary Jane is having a seizure when she starts go go dancing in the middle of a living room and Wade being terrified by the Osborns' brillo hair are just two of the great gags that make up this issue. Kraven is the villain du jour and is a perfect pick because there's plenty about Kraven in the abstract that is ridiculous. But really it's Deadpool's bizarre interactions with the likes of Gwen Stacy and Flash Thompson that steal the show. Before anybody with a scanner and Photoshop could "remix" comics, we had this: 64 pages of sheer hilarity that I'll hold up against anything even remotely similar that has come since. And I didn't even mention the secret origin of Weasel!
DEADPOOL #14 - "In Absentia"
In the aftermath of some truly heinous events, Deadpool snaps and takes it out on Al and Weasel, throwing the blind old lady into a room filled with broken glass, needles and worse--and not for the first time. This issue is all about Al and why living with Deadpool is not funny in the least. It's a total break in style from the comedy of previous issues and truth be told it's issues like this that give the series its depth. We laugh with Deadpool and forget that he is a very disturbed man with an incredibly twisted sense of ethics. Every hero's journey has some sort of "rock bottom" chapter before the climb back to the top begins, but this is different, and it sets Deadpool apart from most characters in comics. Like Al, you can believe in Wade and you can root for Wade, but you can never truly trust Wade. After this story, you will never look at Deadpool the same way again. And poor Weasel...
DEADPOOL #25 - "What The World Needs Now"
On the other end of the spectrum, here is Deadpool in his finest hour. It's the culmination of everything Kelly spent over two years building, and it does not disappoint. Wade gets his chance to prove he's a hero, but it turns out the choices he needs to make aren't easy ones and he ain't getting a tickertape parade at the end of this one: they needed him because they need something killed. He needs to go through no less than Captain America, in a great fight because it swings from the inherent humor of two such polar opposite characters interacting to the very serious burden Deadpool feels when doing the right thing means going against the guy the Marvel Universe considers its patron saint. If "In Absentia" shows why the things that make Deadpool not your traditional knight in shining armor also make him kinda terrifying, "What The World Needs Now" demonstrates why sometimes you need a monster to do the things that the bright shiny heroes can't. Lots of resolution for lots of characters here and plenty of payoff for various Easter eggs, but nothing bigger than Deadpool's big moment and his realization that destiny doesn't intend for him to have a happy ending.
DEADPOOL #27 - "Look! It's Wolverine!"
As the cover says, "...in his most gratuitous guest appearance ever!" Gotta love that this book put stuff like that on the cover. This wasn't the deepest issue, as Kelly was really kinda winding things down at this point, but hey, it's an awesome fight between Deadpool and Wolverine that 'Pool instigates after Logan initially refuses by knocking Kitty Pryde into the air with a move from Street Fighter II. Oh, and Howard the Duck's archenemy Doctor Bong is acting as Deadpool's therapist. Do you really need more sell than that? Well then I can't help you, because you obviously hate joy.
DEADPOOL #33 - "The End of the End or Happy Entrails To You"
Joe Kelly's final issue of Deadpool has Wade in mortal combat with his bitter rival, T-Ray, as they try and untangle their convoluted shared origin in one of the most confusing comics ever. The glorious thing is that I'm pretty sure Kelly meant for it to be that confusing, because about three quarters of the way through, Deadpool just basically says, "Fuck it--I don't understand any of this, but I'm Deadpool, a snarky dude with guns and knives who likes to make wiseass comments and kick people and you really don't need to know much more than that to enjoy what I do!" It's a perfect conclusion to Kelly's run and a brilliant bit of meta commentary in a series that had more of that than you'd expect.
SUPERMAN/BATMAN ANNUAL #1 - "Stop Me If You've Heard This"
Y'know what, I'm not gonna give this one away other than to say that seven years later, Joe Kelly still had one great Deadpool story left to tell, and he told it in the most unlikely of places. Enjoy.