As the show flowed, Mr. Ackermann maintained the straight-backed architecture that makes Tom Ford suits a genuine benchmark for men, while redecorating the facade. Colors were bracing, and fits sat off the body just enough, while underpinnings aimed to startle traditionalists.

For his Tom Ford debut, Haider Ackermann didn’t want only the garments to be sexy. He wanted the glam to match that, too.

At Paris Fashion Week, new designers brought new energy to Tom Ford, Dries Van Noten and Givenchy.