Recruited by Daisy Johnson to join Nick Fury's secret team to fight the Skrull invasion. He was excited at having powers and hoped Nick Fury paid well. He came to hate Nick Fury, but stayed on the team because he fell in love with Daisy Johnson.
After Nick Fury stole $1.2 billion dollars from a HYDRA-owned bank, J.T secretly took some. HYDRA was able to track all the money, and while they were unable to do anything about what was funneled to the secret army Dum-Dum Dugan was building for Fury, they were able to find J.T. They turned him into a double-agent, forcing him to reveal all he knew of Nick Fury's plans.
Nick Fury discovered this, and on their next mission to the HYDRA base Gehenna, he dropped J.T off a cliff when no one was looking.