Great game jam game and POC. Works well - I could almost hear the MGS 'spotted' sound effect in my head. I think your spotted sound effect could be a wee bit more dramatic and that would sell the tension.
Something about the elevator ping to start the level was a fantastic, then the elevator music fades in. I think having location aware music playing would be great. (i.e. continuing the elevator music when you are near the elevator, but then moving to a more tense spy theme when you are out and about? The music can really set the environment I think.
Great work though. I liked it a lot.