>> rohit kachroo in johannesburg. rohit, thanks. >>> when "nbc nightly news" continues tonight, the dangers of a recreational drug called molly. it's big in pop culture and tonight, it's linked to a series of deaths. >>> and clinging to a precious piece of history. how technology is threatening a time-honored tradition. >>> the deaths of three young >>> the deaths of three young people this week at concerts, all suspected overdoses, are putting a recreational drug known as molly, a form of the drug ecstasy, under new scrutiny. nbc's ron mott is here tonight. ron, this is not a new drug? >> reporter: not at all, carl. in fact, it was the '70s and '80s this drug took off recreationally and then exploded in the '90s with a new name, ecstasy. now this refined variety, molly, has only heightened the high and the dangers. its nickname is molly and it's all the rage at techno and electronica concerts. the heady beat of the music, mixed with this adrenaline-pumping drug, has an intoxicating allure for some young partygoers and

. >> well, rohit kachroo, thank you. >>> a stage is set for a meeting between president obama and hassanowhani but will it happen is the question? both leaders in new york city ahead of the u.n. general assembly which begins today. yesterday president obama attended a private event for visiting heads of state and president rhu hani tweeted his arrival seen in the back of the car on his way into manhattan. >>> the country's two top leaders have not met in more than three decades since before the iranian revolution. but rowhani's recent comments are spurring cautious optimism from former president bill clinton especially. >> this new president seems to want a rapprochement with the united states. if we do this, we need this to be real. >> top allies like israel are n unimpressed warning he will try to stall the u.s. while continues nuclear development. >>> two bipartisan groups of high-profile senators wrote president obama warning the same. on the eve of the trip, iran pardoned 80 prisoner, many who have been jailed for protesting the controversial 2009 presidential elections. it's a poss