Stand Up.

Five Reasons Why Tonight's Big Tuck and Tum Tum Show at Dada is a Must-See.

Yeah, we mentioned it earlier today. But it bears repeating: Tonight's show at Club Dada is a very big deal.

In other words: There's a reason they're calling tonight's show The Day Dallas Stood Still.

Five reasons, in fact. Let's count 'em down.

1. Tum Tum and Big Tuck are bona fide Dallas rap legends. Actually, scratch that. These guys are more than just rap legends. They're legitimately two of the biggest names Dallas music can claim in the last 20 years. Each has a fairly deep catalog some 10 years in the making, and each boasts at least one standout, no-question-about-it classic Dallas track — Big Tuck with “Southside da Realist.” They're still going strong, too: Tomorrow, the video for the twosome's latest collaboration, “Yeah Doe” (which also features Dallas rappers Dorrough and B-Hamp) is slated to premiere on BET's 106 & Park, if Tum's Twitter feed is to be believed. In the pantheon of Dallas rap greats, these guys have to be rank near the top, right alongside The DOC.

2. Tum Tum and Tuck haven't performed together in years. Though once attached at the hip as members of the legendary Dirty South Rydaz crew (a group that also included Dallas stalwarts Fat Bastard, Double T, Lil' Ronnie and Addiction), Tum Tum and Tuck each took up a solo career after DSR dissolved in the mid-'00s and, perhaps as a way to separate themselves from their earlier work, they drifted apart. But they've remained friends over the years, as Tum Tum has repeatedly confirmed in interviews, and their recent “Yeah Doe” collaboration confirms that there's clearly no beef here. Still, expect something of a celebratory DSR reunion at tonight's show.

3. Dallas trap rap usually gets the shaft when it comes to shows in legit music venues. It's a shame, but it's true. Much as the backpack Dallas rap community complains about their songs not getting played on the radio, the trap rappers whose songs do get air time have a legitimate response beef: Whereas rock clubs are usually OK with booking a backpack rap bill, they tend to back out when it comes to booking what's often regarded as “harder” stuff. Sure, acts like Tum Tum and Tuck get nightclub gigs that the backpacker set could never dream of, but playing to fans that pay to come into your show and playing to a group of people who are simply on hand to grind on a dancefloor regardless of what music is being played are two totally separate concepts. Really, the best thing about tonight's show is that it merges these two worlds, featuring prominent live acts A.Dd+ and Dustin Cavazos opening up this bill in a sign of unity. That's a significant show of respect out of these young 'uns and, almost without a doubt, it's an appreciated one. In recent years, the only times you'd ever see Tum Tum in a traditional music venue is when a touring, out-of-town act has requested his presence on a bill. This, obviously, is a welcome change of pace. Hopefully, it's a changing of the guard, too. Lord knows Dallas is already way too segregated a place as it is.

4. Not only can you see some Dallas legends, but you'll also be able to see the hottest rappers going in Dallas today. As noted above, adored young Dallas rap acts A.Dd+ and Dustin Cavazos make up the undercard on this bill. And, don't kid yourself, they really don't need to be doing so. These guys can stand well enough on their own two legs, thank you very much. Need proof? Well, Spin just called out A.Dd+ for putting on one of the 20 best sets at Austin's Fun Fun Fun Fest this weekend. Cavazos, meanwhile, may be the hardest working rapper in town: He's made a point of hand-delivering pre-ordered concert tickets and albums to the fans of his that show him that kind of love and, in return, he's developed one of the largest and most loyal fanbases in town.

5. There will be cameos. Promise. This show's promoters have not-so-secretly alluded to this all week long on their social media accounts, so, rest assured, it's happening. But who, exactly, should you expect to see on stage tonight? I'd say Dorrough and B-Hamp — Tum and Tuck's “Yeah Doe” collaborators — are pretty much a sure thing. Cross your fingers, though, that some of the gang from the old DSR days make an appearance. If not, well, pretty much every rapper in town's gonna be at this show already anyway, so it might just be a matter of who Tuck and Tum can spot out in the crowd. And that's not necessarily a bad thing. This show's gonna be one big Dallas hip-hop love-fest. Ain't nothing wrong with that.