welcome back. it is welcome back. it's time to get much closer to a huge great white shark than any of us could possibly think safe, and it's all in the name of science. >> now to do so we go on board the world's only vessel that can capture, tag and keep track of a great white. liam martin of our boston station, wcvb, reports. >> reporter: this is the architect, chris fisher of the history channel "shark wranglers." the goal is to pull great whites on board so they can tag and study them. and on thursday they got the catch of a lifetime. she's been dubbed jeanie, a 15-foot great white. scientists were able to take blood samples, attack this tracking device and an accelerometer to her dorsal fin, and then release her. >> she looks great. >> reporter: researchers have been tracking genie ever since. >> history was made off cape cod. for the first time, spot tagged.