Gribble was in the ROTC. On his Facebook page he posted photos showing him in uniform and holding a "favorite knife."
Anything sharp really, but I love swords and knives," Gribble wrote on Facebook in February.
Friends of the teenagers were shocked that the boys who came from middle class families and participated in activities like school musicals and the Boy Scouts could conspire to commit such brutality.
However, those who knew the teens said they had each undergone a change in temperament in recent weeks going from friendly to darkly menacing.
On his own Facebook page, Gribble wrote: "Although everyone has a light and a dark side, mine are very extreme… If I like you (or at least don't dislike you) I'm the sweetest nicest person ever. But heaven help you if I truly lose it. It's not pretty."
Glover, the Boston Globe reported, was a singer who performed in coffee shops and in a school production of "Cabaret" and Marks was described as "insecure and angst-ridden."
Though it's still unknown how the teens met and allegedly plotted the crime, authorities are moving towards a theory that Spader was the ring leader who influenced the other young men.
Police believe Spader is a young man who cast a strong, negative influence over his peers.
The father of one of Spader's ex-girlfriends remembers him a dangerous character.
"Yes, I've seen violence from him before," Peter Cummings, whose daughter Chelsea dated Spader told ABC News radio affiliate WTKK in Boston.