The Bourne Identity, The Bourne Supremacy, The Bourne Ultimatum, and Jason Bourne) along with the single spinoff starring Jason Renner (The Bourne Legacy) as another member of the same secret government program. While the first film, the closest to Robert Ludlum's source material where an amnesiac Jason Bourne (Matt Damon) left for dead discovers he's an assassin, remains my favorite, all of the films hold up well (even Renner's single film).
The series features strong supporting characters throughout Bourne's attempt to learn the truth about his past including Joan Allen, Franka Potente, Clive Owen, Edgar Ramírez, and Alicia Vikander. Collected in one set, available on both Blu-ray and DVD, the movies include several of the short featurettes and audio commentaries from the previous releases along with a sixth bonus disc.
[Universal Studios Home Entertainment, Blu-ray $69.98 / DVD $38.89]