The Bridge to Nowhere

First things first, hop on the hand car. You'll get a quick tutorial on how it works. Basically, you just need to hold down the [X]/[A] button when Arthur's pushing the bar. Honestly, the easiest way is to just watch the bottom right of your screen; the button icon will light up when you need to press it. Get used to this, because you'll need it later.

Once John heads down below, hop off the hand car. Grab the crate of explosives and head to the side, following the on-screen prompts to lower it. After the second crate, climb down the ladder yourself. This is where things get tricky.

You've got a tight 45 seconds to plant three bundles of dynamite on the marked spots on the bridge. You absolutely have to be precise. If Arthur has to reposition himself even a little, you'll run out of time. Make sure you're ready to hit the [Square]/[X] button as soon as you get near a marker – this saves precious seconds. Do the same when you're grabbing the next explosive. The best bet is to hit the markers in order from closest to furthest. After that, you're really just at the mercy of the game's animations. Expect to try this part a few times before you nail it.

After planting the last bundle, John needs your help ASAP because a train is barreling down. Quickly climb back up the ladder and jump back on the hand car. You need to escape within 18 seconds. This is plenty of time if you focus on the button icon in the bottom right and hold the button as soon as it lights up, rather than watching John and Arthur.

Once you've made it past that close call, follow John to the detonator and use it to blow up the bridge.