Jared Leto has signed up to star in new movie Dallas Buyers Club.
Matthew plays the patient - and has recently been photographed looking gaunt after losing weight for the role - and Jared is set to star as another HIV positive man who meets him in a hospital.
The Motorcycle Diaries star Gael Garcia Bernal has previously been linked to a part as a patient in director Jean-Marc Vallee's film, but it isn't known whether it was the role Jared has now filled.
It will be the first time Jared has appeared on the silver screen since 2009's Mr Nobody, as he has been focusing on his other role as frontman of rock band 30 Seconds To Mars.
Filming is expected to start in New Orleans this month.