[s1e19] Compass -

: To help Frankie process DNA samples while on the run, Mac creates a DIY centrifuge using common items like a bicycle wheel or salad spinner—noted as one of the best "hacks" in the series.

After hearing that Frankie died in a lab fire, Mac travels to MIT with , who is on mandatory medical leave with a broken arm. Their investigative instincts kick in when they notice a suspicious man at the memorial and learn that Frankie's supervisor also recently died in a mysterious car crash. [S1E19] Compass

: Frankie’s DNA research could be linked to future "Phoenix Foundation" cold case files or Mac's own family history. : To help Frankie process DNA samples while