He was portrayed by Emmanuel Avena.
As part of his job assigned by Mr. White, Leo was tasked to help Le Chiffre to reclaim $101,206,000 due to a failed plot to sabotage an aerospace company.
He was first seen entering Casino Royale with Kratt by his side as they hope that Le Chiffre would be smart to earn the winnings and get back into Mr. White's good side and return the money back to Steven Obanno.
However, this was never the case when James Bond kills Obanno and his men, and he has his friend René Mathis to place the bodies on Leo's car to frame Leo for the murders. At the police arrive to the scene, Mathis (watching the scene on a balcony with Bond) places a call, which attracts the police to open the trunk and find the bodies inside. As such, Leo is placed under arrest for the murders, much to his distraught.
Eventually, Bond learned that Quantum was nothing more than a front run by Ernst Stavro Blofeld of SPECTRE, and that Leo, along with White and Le Chiffre, were all pawns as part of Blofeld's true plot to wreak psychological pain on Bond.