This is the MSP( Malogabaritnyj Spetsialnyj Pistolet), from our friends the USSR. The MSP is a break action, double barrel pistol, similar in some respects to a derringer. This gun was adopted by the KGB and Soviet Army in 1972. It is only intended for close range, and would likely not be accurate beyond 5 meters. It is a fairly unique weapon, firing internally silenced 7.62x38mm bullets. The ammunition is known as the SP-3.
Internally silenced ammunition?
Well, the idea is that almost all of the sound that a firearm makes is caused by hot gases escaping from the barrel. A conventional suppressor traps these gases long enough for them to cool and slow down. The MSP uses ammo with a special strengthened case and a gas-sealing piston that pushes the bullet and then locks the powder gasses within the case. This has its drawbacks, and the Sp-3 cartridge only generates velocities of about 600 feet per second, which would severely limit its range and penetration. The gun has a single action trigger and is cocked with a rather strange front cocking mechanism, which sets the internal hammers. Once the pistol is loaded and the breach is closed, the shooter pulls down the lever to cock the pistol and then releases it.
The MSP has no projections or controls to snag when drawing from within a coat or holster. Absent from the design are any form of extractors or ejectors, and spent cartridges are removed by pulling out the small clip that binds them together.
The MSP has little military value as it is only useful at conversational distances, and it is mostly regarded as an assassins' tool. It was replaced by the much more conventional and effective PSS pistol.