In the DVD special, director and actor Noah Wyle says the story was inspired by a Doctor Who episode executive producer Dean Devlin had seen. The interviewer cuts him off when he starts to describe it, but it's clear he is referring to The Doctor's Wife (2011).
Drew Powell (Ray) guest starred in 2 episodes of Leverage, which Christian Kane (Stone) was a main character on though their characters don't interact here.
Drew Powell (Ray) was in ER which starred Noah Wyle (Flynn Carsen)