Called 25i News Today

invites a friend to sleep over. the next morning, shes dead. >> oh, my god! i dont feel a pulse. >> what in the world happened? how could this be? >> turned out this was no ordinary slumber party. >> we know from their phones that this was a planned event. they had discussed it. they took pictures. >> stories surfacing of a dangerous experiment. >> the main purpose of having the sleepover was to try it. >> an experiment that just might tempt other teens. >> we know its entered our high...

>> a bright and beautiful teen invites a friend to sleep over. the next morning, shes dead. >> oh, my god! i dont feel a pulse. >> what in the world happened? how could this be? >> turned out this was no ordinary slumber party. >> we know from their phones that this was a planned event. they had discussed it. they took pictures. >> stories surfacing of a dangerous experiment. >> the main purpose of having the sleepover was to try it. >> an experiment that just might tempt other teens. ...

dangerous experiment. >> the main purpose of having the sleepover was to try it. >> an experiment that just might tempt other teens. >> we know its entered our high school. >> why the clues in this mystery could save a life in your family. >> you have a lot of people watching "dateline" that need to talk to their kids. >> welcome to dateline. parents always worry there are so many dangers out in the world a teenager can face. but at a slumber party in your own basement? how could somet...

As lsd were really a synthetic drug called 25i. >> -- because people dont like that stuff. they think its -- they know its bad, you know? >> but you know its 25i. >> yeah. >> had you ever heard of it before? >> never. we had never dealt with it before. >> reporter: 25i is a new chemical that was only made illegal in the u. s. two months before tara died. it can cause hallucinations, like lsd. but in taras case, it also led to seizures, respiratory distress and ultimately, cardiac arrest. it some...

To students at woodbury high. he admitted to police the tabs he was selling as lsd were really a synthetic drug called 25i. >> -- because people dont like that stuff. they think its -- they know its bad, you know? >> but you know its 25i. >> yeah. >> had you ever heard of it before? >> never. we had never dealt with it before. >> reporter: 25i is a new chemical that was only made illegal in the u. s. two months before tara died. it can cause hallucinations, like lsd. but in taras case, it also l...