Between them, Randy Kaplan and Zoltan Marian have collected more than 2000 autographs of heads of states, royals and popes. They share a kind of ethical code, but differ when it comes to who will they include in their collections.
In a matter of days, Jang Song Thaek went from being one of North Korea's most powerful officials to being publicly denounced as "human scum" and then, according to North Korean state-run media, being put to death.
North Korea on Wednesday announced it's suspending its nuclear activities and missile tests in a breakthrough in negotiations with Washington. Lisa Mullins speaks with Stephen Bosworth, the former US special representative for North Korea Policy.