1. Contact Valentine: easy, medium, hard 
2. Confront and unmask Janus: easy, medium, hard 
3. Locate helicopter: easy, medium, hard 
4. Rescue Natalya: easy, medium, hard 
5. Find flight recorder: easy, medium, hard 

This is a straightforward mission, obstructed by bizarre, Russian constructs, 3D shapes, and the remnant shards of the collapsing communist union. Mission objectives in three the difficulty levels don't differ, except that your life meter runs down faster and bullets that hit you do more damage. 

Turn around and check out the gate. This is where you'll end up at the end of the mission. Turn around and walk into the park, eliminating about four military personnel along the way and picking up a trusty KF7 Soviet. Stay left, pass by a gold star (which you need to remember to get back safely), and under two constructs that appear to be arches. You'll approach a set of pillars and a group of red, blocky letters on your right that read PCCC. Keep going to the left. 

Soldiers will leap out from nowhere throughout the level, but relatively few of them are necessary to kill -- that is, once you become familiar with the markers and shape of the park. 

Within about a minute or so, you'll see a red box-shaped thing on your right; it looks like a shed or an 18 wheeler cargo freight. Enter it to meet Valentin. Now enemies will attempt to kill you while you speak with him. He'll tell you about Janus, and how you need to meet him at Lenin's statue, how Janus is a Leintz traitor, and then he'll walk away. 

The real trick is to get to Lenin's statue. From the shed, it's extremely easy to get lost, so watch for sign posts. Looking out of the shed, turn about 10 degrees right. The first sign is a bright white post directly ahead of you. Go to it, and then proceed along the red fence on your right side. Along this venture you'll be greeted by soldiers, and even on the medium level, they're pretty bad shots. 

The next sign post appears to your left. It's a shiny hammer and sickle, that great Communist symbol. Stay to your right or you'll end up in a cul de sac with a tool shed. Remember, keep along the red fence. To get a handy vest of body armor, look just past the hammer and sickle at an odd-ball group of shapes in front of you. On the left is the back side of a giant hand, and just beyond is another golden hammer and sickle. Walk between the hand and the wall to its right (where you'll find the narrow entrance) to retrieve it. 

Come out, make a 180 turn, and continue the same way you were walking before picking up the armor. You'll reach Lenin's statue in about 10-20 seconds, switching back and forth through the obstacles (the best strategy is to stay nearest the middle, avoiding the side paths). Walk around the statue once and face the path you just traversed. Make sure to go through the weapon selection so that no weapons appears. That's right, you want to meet Janus empty handed. In addition, don't walk to close you Janus, or he'll flee (wuss). Janus turns out to be Trevelyan, your old secret agent associate whom you believed dead in the dam incident. The game follows the movie to a T here. 

Trevelyan will talk about how everyone else is a Leintz traitor, and deliver a message about Natalya: she's at the helicopter, and you only have three minutes to get there. Doh! You may get a little damaged here, but it's possible not to with a bucket load of strafing and running. But first, don't fret, the four henchmen with automatic shotguns aimed at you are not that big of a deal. Really. Pick them off however you want, left to right, right to left. What really matters is that you pick up their guns, five-cartridge shotguns that pack a mean punch. The KF7 is just as effective to get out, possibly more effective, but the shotgun is more fun. These henchmen are pretty much the only opposition between you and the copter now, and instead of just military guys rolling out of the woodwork to kill you, these dudes will, too. Kill them off fast. 

Now to get back. Weave through the constructs until you see the gold hammer and sickle, and then aim a fraction to the left. Once you see the white pillar again (the red fence now should be on your left), aim down the slope so that you can see the red shed where you spoke with Valentin. Make sure it's to your right as pass it. Now you must retrace your steps. Keep running until you see a block structure, which you'll go under. The next set of landmarks are a tall, white pillar on the left and a short, squat pillar on the right. Hey, and remember those crazy red, 3D letters? They'll show up just after those pillars. A white hammer and sickle will appear on your left, so turn slightly to the right and you'll see a red star and a white shed, the next land marks: run between them, then under several constructs. Now you'll see a path beginning -- it'll lead you back to where you started, and just beyond that is the helicopter and Natalya. 

Natalya is lying on the ground to the right of the helicopter. Run up to her and as soon as she begins talking, check the bomb detonation time, and walk toward the gates. She'll follow you. Now there's just one last step. 

You must retrieve the flight recorder, which blew out of the helicopter somewhere in the park. You can leave Natalya at the gates. The recorder is bright yellow (and sometimes red) and appears in different spots on the path depending on what level you're on. The easier the level, the closer it is. In the easy mission, the recorder is resting at the bottom of the hill from the helicopter; in medium, it's farther along, and hiding just beneath a high red construct on the path, in hard, there are more soldiers and it's slightly harder to find. If you go too far, a message will appear indicating that the tape couldn't have been thrown that far. If so, walk back up the hill to find it. 

After you retrieve it, hike back to get Natalya, who's been taken hostage again. Stow your gun (like when you met Trevelyan) and walk through the gate when they ask you to. Mission accomplished.