(Spoilers of course)
...was so well done.
As always there was a slow build throughout that made it feel inevitable. With Jesse waffling and Skyler unwilling to even chat at dinner, Walt has no support system.
In the final moments, the writers took everything into consideration in crafting the action - that Walt would attempt to chat through the issue with Mike first and foremost. That it would take Mike angering him for him to turn back with the intent to kill. That Mike would not give up easily, getting as far as to exit the car before giving in. And that Walt would realize after the fact that he didn't need to hurt Mike when Lydia was still available to shake down. That line made the whole thing heartbreaking (and neatly avoided a plot hole). All of it was extremely faithful to the character they've been building for five seasons and I won't be surprised when this death does not stop Walt's pursuit of an empire.