Death Note, Fullmetal Alchemist: Brotherhood Recommendations
The "chained" events is a common feature in both of the animes and do drive you to think. They share Tragedy and happiness moments that are somehow alike (it's like a projection from the world of fullmetal into the world of death note).
They are both methodical. They make you think and try and figure things out as you go. You never know what will happen next.
Both stories are well-written and neither feel the need to fall back on fanservice or raw action to keep the viewer's attention. Though Fullmetal Alchemist has much more action than Death Note, I'd recommend the two to any fan of deep, enthralling story-lines