[s1e19] Compass -

: The story reveals Mac’s past at MIT, including the fact that he was enrolled at age 17 and had a major crush on Frankie. Further Story Development

: Jack breaks his arm in a trash compactor at the beginning of the episode. This occurs because Mac tells him to hold a pipe "perfectly normal" (a physics term meaning perpendicular), which Jack misunderstands. [S1E19] Compass

: Developing the "hurt/comfort" aspect of Jack dealing with his injury while still trying to protect Mac. "MacGyver" Compass (TV Episode 2017) - IMDb : The story reveals Mac’s past at MIT,

: Frankie’s DNA research could be linked to future "Phoenix Foundation" cold case files or Mac's own family history. [S1E19] Compass