United Kingdom, June 2 -- Jon Hamm's 'Mad Men' co-stars turned "yellow and sallow" after attempting to smoke real cigarettes on screen.

The 54-year-old actor - who led the cast of the 1950s advertising drama for its entire run from 2007 to 2015 - went through dozens of fake smokes, made from rose petals and marshmallows, during filming but he fared better than some of his unnamed co-stars who were keen to make their experience more authentic.

Speaking at the ATX TV Festival in Austin, Texas, at the weekend, he said: "I think somebody did a count, and in the pilot alone, I smoke 75 cigarettes.

"They are fake cigarettes, but that just means that there's no nicotine in them. It doesn't mean you're not burning something."

Of his castmates...