Intrusion S01E03 - Cacophonie

The electroshocks have accentuated Marc/Philippe's hallucinations: he sees the car accident that killed his brother. Convinced of being the victim of a conspiracy, he escapes from the hospital and returns to the cottage of their childhood. The trauma comes back to him. Philippe was the favorite, and when he died in the accident, little Marc took his place, posing as his dead brother. He spent his whole life in the skin of the one he was jealous of. The shock makes him again switch to another reality, that of Philippe, the pianist. How do you know who he really is?