Sadly, this house got torn down. https://www.oldhousedreams.com/2013/02/26/1962-contemporary-croton-on-hudson-ny/ Per the comments near the end, “As with many unique houses it cost too much to keep up and my elderly parents let it fall into disarray. We could not fix it up when my mother died in 2012”
“handrails were deliberately left off to allow the defender to push the attacker off the stairs all together. Also violating all modern building codes, stair treads were sometimes constructed of varying heights to deliberately cause attackers to stumble and fall as they ran up them.”