We get there and it's super crowded; we have to wait about 15, 20 minutes for a table. Not a big deal, since we have a rather large party (10 all told, although a couple of them aren't there yet, so it was actually nice of them to seat us without those people. We get to the table and there are no menus, but as it's busy, we're prepared to wait. Shortly after we get there, another smaller party is seated next to us; they are drunk, and we have to fight them off to keep our extra chairs, since they try to take them without asking if anyone's sitting there. (Not the restaurant's fault; just another annoyance.)
The waitress comes up (not our favorite one, sadly) within a few minutes to take drink orders; we mention to her that we have no menus, and she tells us she'll get them as soon as she can - her excuse was "Well, we have a lot of big parties right now, so we're short on menus." First of all, why would you not have enough menus for a restaurant close to capacity? Second, there are people out waiting for tables who have menus, as well as people who arrived after us. Strike one for Denny's.
The rest of our party arrives, and we ask them to grab us the menus that are lying on the table next to us, which has for some reason been vacated by the drunk people. We share menus and water arrives, but no other drinks, and no one comes to take our order for maybe another 15 or 20 minutes after that. In fact, we really don't see anyone for that time, except rushing by to other tables.
Finally, our waitress comes back with the rest of the drinks, and we order. I get loaded cheese fries with sour cream, an additional drink, and a new seasonal item called "gingerbread pancake puppies". L, the friend next to me, orders a grand slam with several other seasonal items. Everyone else orders straightforward things from the menu, without any additional specifications. This is important.
Again with the disappearing waitresses. We get maybe one drink refill in the next half hour. All told, we end up waiting about an hour and a quarter from the time we sit down to the time we actually get our food, and then a different problem begins.
First, I get the wrong drink; I ordered a strawberry mango drink that includes orange juice and I get one that includes Sprite. I don't actually complain about this one because it's a minor mistake and a fairly easy one to make in a noisy restaurant. I also am missing the sour cream for my fries, and the pancake puppies do not taste remotely like gingerbread. (In fact, they kind of taste like potpourri). L's order was supposed to include orange cranberry pancakes; she gets what looks like regular pancakes. She checks with the waitress to confirm that they are the right pancakes; she says yes. Her order is also missing French toast and a ham steak, but she ends up with an inexplicable order of hash browns instead. My boyfriend P and his friend D ordered similar burgers, both of which were supposed to come with hash browns and eggs on them; one burger is missing the hash browns while the other was missing the eggs. The waitress seemed very confused as to what the problem was and they had to explain it three times. All in all, about half of the orders came out wrong and had to be sent back, or were missing crucial parts.
L mentions to the waitress on her next trip that she's still missing two parts of her meal; it turns out that the hash browns came out in place of something else she ordered that didn't sound remotely like "hash browns". She also points out that her cranberry orange pancakes do not, in fact, have cranberries in them; the waitress finally explains that they don't actually have any cranberries. Since when is it good service to just give someone food without a crucial ingredient and hope they won't notice? P and D finally get their burgers sorted; at this point I am too hungry to wait until I get sour cream for my fries, so I just eat them. L finally gets her French toast, which is fine, and her ham steak, which is cold.
At the point when the food first arrived, one of the guys in the party asked to see the manager, since by that point there had been no explanation or apology for the ridiculous wait. He asked twice more in the next 20 minutes or so, and in the meantime the waitress had brought our check, which was all one ticket. (Common practice for Denny's, which is kind of annoying, especially considering I know they do have the capacity to make separate checks; they just rarely ask if we want them.)
We all go up to the register to sort it out; L is pissed because she does not want to pay for her botched meal and we still haven't seen the manager. We wait at the empty register for another five minutes or so. Finally, the manager comes out of the kitchen, where it turns out he's been frantically working to try and make up for the backlog of orders (score one for him) and listens to us. He comps L's meal and a couple of others within the party, and we find out through his explanation that the day manager, who is in charger of scheduling, decided to only schedule three waitresses instead of the usual five on what was probably the busiest night of the semester. I can only imagine what the shortage on kitchen staff might have been. (I did leave a tip for our waitress, although it was a small one; the slow service wasn't entirely her fault, but she made her own mistakes, too.) So, because of the manager, this was bad service turned good
I may not have the timing exactly right on this, since I didn't write down all the times, although I probably should have, but suffice it to say that we were seated at 2 and didn't leave until almost 4.
(Strangely enough, this is not going to prevent us from going back to Denny's; we've been there late at night dozens of times and this was the only real bad experience we'd ever had.)
tl;dr Late-night Denny's is understaffed; we wait over an hour for our food, waitress and kitchen staff screw up or forget orders and make odd excuses for mistakes. Manager makes everything somewhat better.