S4, E8: When Hiro (Masi Oka) travels three years into the past, he has a second chance to save Charlie (guest star Jayma Mays) from the hands of Sylar (Zachary Quinto). However, Samuel’s (Robert Knepper) presence serves to complicate Hiro’s mission even further. Elsewhere, H.R.G.'s (Jack Coleman) past with his Primatech partner (guest star Elizabeth Rohm) is revealed. James Kyson Lee, Hayden Panettiere and Sendhil Ramamurthy also star. Danielle Savre, Sally Champlin and Dawn Olivieri also guest star.