This is designer-casual territory and the wait staff are just as respectfully precise and formal. More importantly, though, Tomoji Ichikawa remains in charge overall, which means the focus on French cuisine is unchanged.
As his head chef at Atelier d'I, he's brought in Keiji Ota, who used to run the kitchen at the now-closed Marunouchi branch of Labyrinthe. He's got a great touch, and delivers a delectable menu of robust, modern brasserie fare that dovetails perfectly with the wine selection.
The great thing is that you don't have to order a full meal as soon as you sit down: You can pace yourself, pick a couple of starters or skip straight to the cheese plate. That's what makes L'Atelier d'I a wine bar, not a restaurant. Better yet, it's not a wine- snob sort of place. You don't have to spend hours poring over the list and, apart from a couple of trophy burgundies, there are only a few bottles above the daunting ¥10,000 mark, and a good many for almost half that much.