Plot hole: At the end of the episode, the trooper answers the phone declaring the bridge is safe to cross but the driver is still worried. The trooper says "We'll go on ahead, cross the bridge first." When Mr. Ross returns to the diner, he tells Haley the bridge wasn't safe. It collapsed. The state police car, the bus, everything went into the river with no survivors, except him of course. Here's the problem. The troopers were going to cross the bridge first to check its safety, then let the bus cross (1 vehicle at a time). That means only one vehicle could have made the bridge collapse, not both at the same time. If the police car made it across safely, then the bus caused it to collapse. If the police car caused it to fall, the bus would not have gone anywhere near the bridge. Therefore, the story Ross gives Haley throws off the whole point of the police going across first.
Plot hole: The street sign in the beginning is all wrong: it faces the camera rather than the street where the story takes place. In a typical American city, street signs are almost always placed in the direction of the street they are indicating, so drivers on the other street in the intersection know what they are turning onto or passing. In other words, the story is not set on Maple Street! Maple Street is the intersecting street at the end of the road the story is set on.
Plot hole: If Walter was indeed immortal from his deal with the devil then there was no reason for him to use the Escape Clause when he was sent to jail. Since he can't be killed by any means and nobody can harm him there would have been nothing to stop him from escaping the prison the moment his cell was opened.
Plot hole: How did the brother know where his sister and her husband were located after he escaped and jimmied open their door? The couple was staying in a hotel and they acted like they hadn't seen him in quite a while when he appeared on the picture of him walking in the room. They said he couldn't possibly walk through the door because he's been in prison for a year already.