S4, E16: Hiro’s (Masi Oka) life hangs in the balance as his brain tumor worsens, prompting him to subconsciously deal with some of his past decisions. Meanwhile, Sylar (Zachary Quinto) pays Claire (Hayden Panettiere) an unexpected visit to get answers as to why he isn’t quite himself. Elsewhere, Samuel’s (Robert Knepper) plan to impress his long-lost love, Vanessa (guest star Kate Vernon), takes a terrifying turn. Jack Coleman, James Kyson Lee and Sendhil Ramamurthy also star. Lisa Lackey, Danielle Savre, Sally Champlin, Satomi Okuno and Jordan Dang also guest star.