A Certain Scientific Railgun A Certain Scientific Railgun T Episode 20 Ha Det Bra ( Air Date 2020-08-21 ) Genre Animation, Action & Adventure, Comedy, Sci-Fi & Fantasy category. Overview "Frenda and Saten find themselves under fire from an unknown assailant, and duck into a department store to find cover. When none of Frenda's usual tricks seems to work against their pursuer, she has no choice but to resort to drastic measures.".