In Back to the Future ( 1985) Lorraine calls Marty McFly as Calving Klein because of the underwear. In that year CK wasn't famous outside the US, thus they changed it to

DeLorean Hire - Hire from Sandstone Productions

Calvin Klein, Futurepedia

Calvin Klein, Futurepedia

NewtCave: Recap: Back to the Future Part 3: Present Perfect

NewtCave: Recap: Back to the Future Part 3: Present Perfect

Back to the Future (1985) - FAQ - IMDb

Why doesn't George McFly suspect Lorraine of continuing an affair

Marty McFly Calvin Klein Scene: Hilarious Back to the Future

In Back To The Future, why do people keep calling Marty McFly