For this special crossover episode, Tim is joined by the one and only Roman Mars to discuss his new series, A History Of The United States In 100 Objects. From a safe that stayed locked away for a century to a well-intentioned milk carton that terrified a nation, each item reveals a fascinating piece of American history - and comes with its very own cautionary tale.

Listen to  on the 99% Invisible feed, or on BBC Sounds.