#4 Johnny Gargano
2017 saw Johnny Gargano establish himself as NXT's most lovable underdog. His story arc has been told perfectly. Betrayed by his teammate, Tommaso Ciampa, he was forced into a singles career that saw him take a long string of high profile losses.
He came close, but could never win. He finally looked set to reverse his heartbreaking losing streak in December by becoming the #1 contender to the NXT Championship.
But this will prove to be a false dawn. The man who betrayed him is waiting in the wings and will almost certainly screw him out of the title just on the cusp of his triumph, beginning a long and bitter rivalry that could well rank as 2018's best.
It will only further serve to make Johnny Gargano WWE's most sympathetic character, and his eventual title win late next year or early in 2019, all the sweeter.