[Utsuro no Hako]

Originally Posted by fertygo

Steins; Gate start very slow too.

Spoiler for First Episode of Steins;Gate:

But it did a better job of hooking viewers with "WTF is going on here?" moments right from the first episode. Even Chaos;Head managed that in the beginning -- the series didn't fall apart until it tried explaining everything.

But R;N didn't even try to set up a mystery, unless you count the obligatory, "Ooo, who is this mysterious stranger" scene at the end.