This is Soviet Project 661 Anchar, K-162 (Nato - Papa class) missile sub. The sub was a one off experimental design predecessor to the famous Alfa class. It still holds the record as the world's fastest sub having made 44.7 knots submerged.
The kit is from Samek that I built as a relaxation project so I didn't do anything crazy (through I did have thoughts of opening up the hull to show missile tubes :) ). The build was straight forward - the hull was waterlined and all of the small parts were scratchbuilt. I've found some really good close up shots of the sub at speed in the US DOD archives and since the sub was supposed to be very fast I decided to show it at speed.