After studying biology and philosophy at the University of Leuven, Thomas attended drama school at the Antwerp Conservatory, where he graduated in 2006.

Since then, he has worked with theater directors such as Ivo van Hove, Eric De Volder and Lucas Vandervost, and film and television directors as Martijn Maria Smits, Hans Herbots and Nathalie Teirlinck. 

Notably, he has played in the short Venus vs Me (2010) winner of the Best European Short at the Berlin film festival, and had a leading role in the international drama series The Spiral (2012), which was nominated for an Emmy award.

He has had leads in the Telefilm Groenland (2015), the Dutch-Belgian co-production series Als de Dijken Breken (2016) and the feature Waldstille (2016), which premiered at the San Sebastian Film Festival in 2016. On the subject, the Hollywood Reporter wrote; “This film compels our attention because of expert acting and directing. The film’s strongest asset is Ryckewaert’s performance in the central role”. Thomas was nominated for Best Actor in the Golden Calf competition at the Dutch Film Festival in 2017 for his role in Waldstille.

In recent years, Thomas has starred in the International success series The Serpent (2021), State of Happiness II (2022) and ARCADIA (2023).

Currently, Thomas stars in his solo-performance Chaos and he’s working on his new performance Annihilation.