Amid growing concerns about global warming, nuclear fusion is once again in the spotlight as an emissions-free energy source. The development of fusion reactors is now within our reach. One of the key persons in this field is Toshiki Tajima, who resides in the United States. The venture company where Tajima works as Chief Science Officer (CSO) is attracting attention from all over the world. Tajima is not an engineer, but a physicist world famous for his discovery of "laser wakefield acceleration" (LWFA). His paper published in 1979 is one of the most cited articles in plasma physics. Professor Tajima is 75 years old now, and he is still at the frontline of theoretical physics. In this episode, we will see two different facets of his research: in academia and in a venture business.