The youngest son of actors Irène Jacob and Jérôme Kircher, he is known for his starring role in Catherine Breillat's relationship drama Last Summer (2023), for which he received César Award and Lumière Award nominations.
He grew up in Paris with his brother Paul, who is three years his senior and is also an actor.
[3] Kircher made his screen debut in 2023 in Catherine Breillat's erotic drama Last Summer (L'Été dernier), a remake of the 2019 Danish film Queen of Hearts.
[4] Théo is a fragile figure, and as time passes, the relationship turns destructive.
Paul then recommended Samuel, who was not active in cinema, to the director, who ultimately awarded him the role.