story sounds like it is made for tv, in some ways it is. he is very, very smart, possibly smarter than sheldon. reporter: iain armitage plays sheldon cooper. but when the cameras aren t rolling, he calls elliot, a regenius, his friend, a bond formed when came to visit the set and stayed strong since. ian is a great friend. the thing i love about the young sheldon is it really makes being a nerd cool. reporter: when elliot is done studying at the u, he dreams of once again returning, again as a professor to share his passion with others. i feel like i would love to be able spread some of this joy for physics and enthusiasm around. reporter: c caroline cummings, cbs news. being a nerd is definitely cool. way to go, elliot. elliot next on