When this chapter begins, you'll be on a beach with Henry, Sam and of course, Ellie. Head down the beach to where you'll find a boat, making sure to search it thoroughly, but not forgetting to check every nook and cranny of the beach as well.
Meet up with Henry and give him a hand gaining access to the sewers. Keep your eyes peeled for a small waterfall to the right, then make sure to explore it before moving on. When you continue, take the right fork with Ellie, then help her gain access to the blocked room by using the air vent to the left. You definitely don't want to pass this area up because you could miss out on a large amount of Parts.
When you exit the room, take the path directly in front of you to meet up with Henry and Sam again. Follow them through the sewer until you reach a body of water. Try the wheel, which will let you know that the large gate is jammed, then jump into the water, dive under and remove the obstruction. When Henry opens the gate, swim through and go right when you hit land. There should be a small stash of supplies nearby. Go back to the left and up the ladder to find a wooden pallet that you'll need. Knock it into the water, then turn your attention to the door. When you open the door, toss a Molotov inside to kill the two Infected. If you miss any, just clean them up with one of your guns.
Search the room for supplies, then hop back in the water and take the wooden pallet to Ellie, ferrying her across to where the generator is. When she fires it up, Henry and Sam will travel across, then Henry will help pull Joe from the drink so the four of you can continue your journey.
Tip: Search every inch of the sewers, there are a lot of supplies, including a new weapon, Tools Level 3 and even a Training Manual. If you don't have all of those when you leave, you're not in as good of shape as you should be.
Continue moving along the only path you can, but make sure to duck into a door on the left when it pops up. This door will have some Parts, but most importantly, Tools Level 3, which will allow you to upgrade your weapons even further. With the room cleaned out, get back to the path and continue your journey.
After going through some double doors you'll trigger a noise trap. This is your cue that a few more items of interest are just ahead, and extreme vigilance is needed while exploring. For example, a few feet ahead and sitting on a table will be the Shorty, a fairly useful little shotgun that you will likely find beneficial as you continue your travels. A few feet further and on a shelf to the left you'll also find the Training Manual: Bombs Upgraded.
Further on you'll find another area with some supplies, and beyond that, an iron gate. Open the gate and head through and down the stairs. As soon as you do, several Infected, including a Clicker will come after you. A well placed Molotov should take care of most of them, then be sure to check the side room with all the blue barrels for any goodies that the previous inhabitants left behind. Once your pockets are filled, head back to the main part of the sewer and continue.
Move along the sewer until you find another closed door. Go inside and loot it, then get back to Henry, Sam and Ellie. A bit further ahead you'll open a chain link door, setting off a trap and getting the group separated. Henry is now with Ellie, and Sam is now with you. This will probably end well... right?
When the cut scene is over, go through the chain link door, but stay right next to it. This area is absolutely crawling with Infected, and rather than mess around trying to stealth kill them all, we're going to show you how to funnel them into a kill zone.
Tip: Before you do anything, spend a moment crafting Molotovs, Bombs and anything else you can until your inventory is full. Also, make sure to fully reload all of your weapons so that you don't have to fuss with it during this battle. It's really not that hard, we just believe in being prepared.
Just inside the chain link door -- the side closest to the Infected -- throw a Brick or Bottle to get the attention of at least one foe, but hopefully more. When they come to investigate, hit them with a Molotov. This will create a wall of fire between you and your adversaries. Since most Infected are set off by noise and lack great vision, they should run right into the inferno and burn to death. If you get more coming your way but the fire is burning out, throw another one, or even go for a Bomb if there is a large cluster of them.
There's a good chance you won't get all of the Infected, so when they bulk of them have been cooked by your Molotov, use Joel's focused hearing to locate the rest, then systematically choke or Shiv them to death until you get the all clear. As per usual, make sure to loot this entire area before moving on and boosting Sam up to the ledge.
Tip: Before boosting Sam onto the ledge, but after everyone is dead and the area is looted, take another moment to craft anything you can, especially Molotovs, then bombs secondly. You may not have a chance to do this again before you need them.
When you jump back down into the sewer, you'll be reunited with Ellie and Henry, but they are definitely not alone. Run with the group away from the Infected until you reach an obstructed gate. Sam will get you out, so continue sprinting along the only path you can take. When you reach the exit and find that you can't get through, turn around and get ready for a fight.
The good news is, the advancing Infected have to funnel through a small area, which means that you can once again use the Molotov to burn them up before they get too close. Bombs work well too, but they are over in a flash and are much harder to be accurate with. Beyond those items, your Shotgun is your best friend and will devastate the advancing scum with well-placed headshots.
Pay close attention to Ellie and Sam's voices, and when they tell you to move, turn and go out the door. It's an endless amount of Infected, so the only way to break the engagement is for you to turn and run. Once you're out the door, you should be relatively safe for a while.
Tip: This next area is fairly clear, but any time you finish a big fight like that, make sure to reload your weapons and craft anything from the supplies you have. This will allow you to pick up more along the way.
Now that you're outside, you'll find yourself in the suburbs, which makes sense given the title of the chapter. Your best bet is to stick to the street, making sure to hit every open house that you can. Most of them contain at least some looting items, as well as Artifacts and other collectibles.
As you continue along the street, you'll come to an open garage, and inside will be a crafting table. We would advise that you loot this house and the next one before you use it. Also, don't forget to check the back of the pickup truck in the driveway, you never know what you'll find.
Tip: The Next house after the crafting table has a safe on the second floor. Go to the third floor to find the Matchbook, then head back down and open it. Inside you'll find more parts that will benefit you at the crafting table one house back.
While you're in the house with the open garage, make sure to go all the way up to the second floor and interact with the attic door. Joel will boost Ellie up, and when she returns, she'll have the Training Manual: Melee Techniques.
With both houses looted, head out the back and drop down onto the next street. This will trigger a sniper, and in order to take him out, you're going to have to flank him. As soon as you gain control of Joel, go to your right and take cover behind the El Camino, then move up to the stack of firewood just in front of you. For this operation, we'll guide you along the right flank.
Tip: When moving up, wait for the sniper to fire, then make a run for the next piece of cover. If he hasn't fired in a few seconds and you make a break for it, you might be taking a bullet to the dome. Not good.
Make your way into the first house on the right, but be very careful since a heavily armored Hunter is not far away. You're going to want to go for a headshot with this guy, then loot the house and make your way out the back, taking cover behind another pile of wood a little closer to the sniper.
Tip: If you really feel the need, this is the perfect situation to utilize Smoke Bombs when moving from cover to cover. Quite frankly, while they are useful, we rarely use them, and this is as good of an opportunity as you'll get.
The next house can have up to four Hunters, and they will flank you. Consider upgrading your melee weapon to give you a one-hit kill in hand-to-hand combat, but other than that, the Shorty and Shotgun are where it's at. Headshots should give you one hit kills, where as body shots might take two or even three.
Continue to move along, clearing out the houses and stay as far to the right as you can. There will be more opposition, but as long as you stay out of the sniper's field of view you should be able to take them out. When you get to the row of houses where he's located, go around and into the back yard. Clean out any remaining Hunters, plus loot the house next to his, then head inside to find this dude and dispose of him.
As you go, continue to search the house and make your way to the nest. You can't see this guy with your hearing, but when you get close he'll jump you. Follow the on-screen prompts to kill him.
Now for the fun part. Grab the sniper rifle and turn your attention to the street, providing much-needed cover for Ellie, Henry and Sam.
The first wave will just be additional Hunters, and they come from straight ahead to start, then from the left. After you've killed enough of the foot soldiers, that dreaded Humvee from Pittsburgh will return. Don't bother trying to shoot it right away. Just keep taking out Hunters running through the yards. When the dude in the Humvee pops his head out to throw a Molotov, hit him with a sniper round to burn everyone in there alive.
Don't let your guard down yet. Fairly soon after the Humvee is down, some Infected will rush your friends. Focus on taking out the one that jumps on top of Henry, then look further up the street to take out the hoard that's advancing. For this part, it's best not to zoom in, as the targets get so close it makes aiming very difficult. After a few shots and hopefully some kills, a cut scene will play and signal the end of the chapter. When you're ready, head off to Chapter 7: Tommy's Dam.