They started by going to the Sleeping Giant Inn in the early morning to apprehend any and all Redcloaks they could find there. Their first target was Erik, the Redcloak they had waylaid when he was leaving Cragmaw Castle some days before, now dubbed "Erik the Unfortunate" by Morgo for his tendency to be standing in the line of fire when the PCs went off. A short bit of intimidation on Gimlet's part (bolstered by the fact that Erik remembered the trouncing they gave him before, and by Erik rolling very poorly to resist) persuaded Erik and his buddy to make himself scarce. Then the PCs went from room-to-room in the tavern, quickly subduing Redcloaks (most of whom were fairly subdued already from their late-night carousing).
Also at the inn, the PCs noticed a peculiar fellow in purple robes with a black leather bat-wing motif cloak, looking somewhat like Count Olaf from the Series of Unfortunate Events books, cackling to himself and eating what could only be described as "an evil breakfast." When they asked Erik about him before the Redcloak was scared off, he told the PCs that the guy was a loon who had wanted to talk to Glass-Staff, but that was all he knew. Evil Breakfast Guy mostly ignored the PCs, however, so they mostly ignored him in return.
While Morgo and Elsa waited for Tylow, Gimlet, and Mei to round up the hung-over Redcloaks, they had a very pleasant chat in which it came to light that Elsa was from the People of the Wolf, and that she'd left home because she'd been betrothed to marry a half-orc from the People of the Boar, but that she had really not wanted a husband with tusks.
Once the Inn was cleaned up (removing roughly 60% of their current patrons), the party moved on to the hideout in the catacombs under Tresendar Manor. The catacombs had two entrances, one through the cellar under the manor ruins, and the other a cave entrance from the beach. The PCs jammed the cellar door and scattered caltrops in front of it to hamper anyone's escape, something that would come into play later, then headed for the beach entrance.
The cave was guarded, something that the Redcloaks had added since Tylow's time with them, but the PCs quickly made short work of them (taking one prisoner), and moved on inside. They quickly and efficiently made their way through the catacombs, being only slightly creeped out by the Thing In the Pit which kept telepathically hinting that it knew their secrets. (As the PCs are relatively upright, or at least straightforward about their intentions, this sinister probing rather fell flat. It's hard to prey on the conscience of someone who's not feeling particularly guilty.)
Finally the PCs reached Glass-Staff's quarters and burst in, discovering a workshop with several Redcloaks and– Erik? Again? And why did he change his shirt? Battle naturally commenced: Erik fled to the next room, where Glass-Staff was, sucking up considerably more hit points than he'd been able to in their previous encounter.
Glass-Staff quickly cast a hold person on Gimlet, effectively turning the dwarf into a giant doorstop for a few rounds, long enough for Glass-Staff and Erik to shove a desk in front of the door and make their getaway through a secret passage. Mei and Tylow slaughtered the rest of the Redcloaks (except for one who surrendered, curling up into a ball as Tylow kept pounding on him in an ineffectual strike-to-subdue mode), then the party turned their attention to smashing down Glass-Staff's door. It was a tough door! It finally took three of them aiding Elsa, who in turn had to use one of her rages to smash the door in.
Glass-Staff and Erik had a five-turn head start on them by this point, but the PCs were not ready to give up. They followed the secret passage on the run, getting back out to the pit, where Tylow rolled a 20 on his listen check and heard the escaping criminals bashing down the cellar door the party had blocked before coming in.
The dice were rolling hot at that point, because when I had Erik roll to bash the door down (with advantage because Glass-Staff was using the help action), both dice came up 20! So they only lost one turn banging on that door (as opposed to the five turns the PCs had lost bashing on Glass-Staff's door), but then ran headlong into the caltrops, heartily cursing the PCs at this stage (not that the PCs had arrived yet to hear that, of course).
When the PCs reached the cellar door, they found that Glass-Staff and Erik had managed to get through it, but Mei and Elsa spotted a trail of blood where one of the fleeing criminals had stepped on the caltrops, and they followed the trail into the ruins of Tresendar Manor finding, much to their surprise, Lord Sildar, binding his feet. Lord Sildar pointed off towards the town, saying "They went that way!"
Tylow followed that lead, but the rest of the party decided there was something strange going on here and started interrogating this "Lord Sildar." Although his answers to their probing questions seemed legit enough ("You said you were coming to Tresendar Manor, I came down to see how you were doing and ended up stepping on those stupid caltrops!"), Morgo used detect magic and determined that there was definitely some sort of polymorph in action. Deciding that enough was enough, the wizard cast witch bolt on "Lord Sildar," whose hobbled movement would make escaping the spell's effect very difficult.
"Lord Sildar" shrieked and gave in, shapeshifting into the form of the same female drow the party had encountered at Cragmaw Castle, who declared Morgo "Rude!"
Presumably this shapeshifting drow was who had been posing as Erik, and the real Erik really had run for it after the encounter at the Sleeping Giant. When Morgo demanded to know what she was doing in the Redcloak hideout, she replied that it was none of their business, leading to some entertaining banter about whether or not one should hold a grudge for associating one's enemies, as well as the distinction between "aggressive negotiations" vs. "being a bad guest."
Tylow, meanwhile, managed to catch a glimpse of Glass-Staff reaching the edge of town. The Redcloak leader, when he spotted Tylow, quickly quaffed a potion of invisibility and was gone. Tylow came back and rejoined the party, and they all regarded their new prisoner, trying to figure out what, if anything, to do with her. We ended the session there.
Five sessions in, still loving 5E. The Redcloak hideout as written was a level 1-2 mini-dungeon, which I basically beefed up for the 3rd-level party by adding a few more Redcloaks in each room, and adding a few where there weren't any originally (which made perfect sense in the context of the campaign as it has unfolded: pretty much the whole Redcloak organization was in hiding down there). Combat is fast and fun, with advantage and disadvantage still ruling the day, and planning plus good tactics is much more useful than simply picking your biggest power at the beginning of the fight and blazing away.
By focusing on the entire dungeon as an adventure site, rather than on each room being its own, large, set-piece encounter, the situation becomes much more dynamic and the actions of individual characters become much more important. I'm definitely feeling more immersed in the story and less like I'm simply moving pieces around on the board.
My one worry is the rate of progression: in just five sessions, the characters are now halfway between level 3 and level 4– I don't want them to skyrocket past all of the content I've generated! I knew levels 1-3 would go by fast, that's an intentional part of the game design, but now we're heading for level 4 at a breakneck speed and the characters have barely scratched the surface of Pelann or Cragmaw Castle, and haven't gone anywhere near Wave Echo Cave. Looking at the progression chart, it does appear that leveling slows down noticeably after 4th level, tho, so we'll see how it goes.
I don't want to never reach the higher levels, by any stretch, I just don't want to feel like the game is racing to get there. I like this character group and this campaign, and I want it to last.