Yes, my game is original, both in terms of story and game mechanics.

If implemented properly, it will ooze money.

But you are right, publicizing the game as my own will help greatly in this regard, but this will come much later. Before that phase it will be under a lock-down.

19 minutes ago, Armantium said:

If implemented properly, it will ooze money.

So then why not spend the money in getting the legal documents and lawyers you need?

40 minutes ago, Armantium said:

If implemented properly, it will ooze money.

Implementation is by far the most important part of any game.  Good implementation of a rehashed idea will be far better than poor implementation of an original idea.  And if an idea is never implemented at all, it's guaranteed to make zero money.

My point is, don't get so paranoid with protecting your idea that nothing ever comes of it.

I know this is an unsatisfying answer, but it's:
"Hire professionals with a track record."
That will cost you more than if you took the cheapest bid from "a few freelancers from several different countries" but it will also cut the odds your game will be stolen to close to 0.

People who do this for a living aren't going to steal your code/art/sound.

4 hours ago, Armantium said:

If implemented properly, it will ooze money.

If you're THAT confident that your idea is worth that much, then you should be able to borrow against your future success and hire the proper experienced devs and legal assistance to solve your problems.

I would be VERY careful with that level of confidence though.  "If implemented properly" presents a big risk.  Everyone has all the best ideas, but unless you've got the experience to back it, and you're lucky enough that nothing goes wrong (whether or not that's really luck is a whole other conversation), then the ideas aren't worth anything.

The biggest difficulty about legal agreements is the cost of enforcing them.

•  Getting a well-written NDA that covers all your issues might cost a few hours of lawyer time. That's a couple hundred bucks.
• Enforcing an NDA within your own local courts might cost tens of thousands of dollars (on the cheap end). 
• Enforcing an NDA internationally using international courts might cost hundreds of thousands of dollars (on the cheap end).
• Collecting on damages for an NDA violation will have yet another cost, but will only be successful if the ones being sued have resources.

Let's say your local game contractors break their NDA. Your costs to collect on the damages are relatively low and there is a high chance they have assets you can collect on. If you were careful about everything you can pierce corporate veils and be able to collect even if it means adding liens against their property, including homes and vehicles.

Additionally the local game company can fear the damage to their reputation, as you can ensure the breach is covered in all the appropriate media and discussed by all the contracting hubs.  They understand that the breach will cost them severely, possibly including costing their business.

Now let's say a small game contractor in another nation breaks their NDA.  Your costs to collect on the damages are relatively high and there is a low chance you'll be able to collect anything. Even if you are careful you are unlikely to collect anything unless you incur an extreme investment to enforce and collect the funds, and even then the company likely has few assets to collect from.

The remote game company has little to fear for their reputation as they have a global pool of customers who are unlikely to see any discussions of their breach.  If you take further steps to notify other companies of the breach (beyond media outlets and posting on contracting hubs) it can be you on the receiving end of a lawsuit. It is illegal in most places of the world to interfere with a business contract, and tortious interference can leave you on the hook for more than the entire cost of their other business deals.

Agreeing with the others, the safest approach is to work with professionals who have an established track record. That can include professionals in other countries who have an established track record of trust. The groups have demonstrated they are trustworthy, and can generally be trusted even without demanding a full NDA.  Their experience shows them the value of keeping trust, and they would lose their business quickly if they violated it.

This is a question every developer struggles with, and I'm a bit late, but it never hurts to let an actual lawyer chime in on the topic. 

For adding new team members, you may want to consider a "collaboration agreement". 

If you're just hiring freelancers, you'll probably want a work-for-hire agreement. 

If you're concerned about enforcement, try not to hire outside of Berne Convention signatory countries and make sure your contract's choice of law and jurisdiction rules are local to you. But if you don't have tens of thousands or hundreds of thousands to spend on legal enforcement, this is going to be difficult in any situation, regardless of where the freelancer is located. 

There are both technical and legal ways to protect your code more extensively than through the letter of an agreement, as well:

1. DRM and other copyright protection software that prohibits copying and/or constrains access;

2. Use of escrow accounts for code and payment;

3. Strict liquidated damages provisions in the event of breach of confidentiality/non-disclosure (this is a specified monetary penalty if they breach-- if you want to be REALLY anal you can require they post a bond into an escrow account, but no one would sign that);

4. Strict liquidated damages provisions in your non-compete/non-solicitation clauses. 

5. MAKE SURE THEY HAVE INSURANCE (PLI/E&O, preferably with a Cyber liability rider to cover data breaches), and make sure you are a named beneficiary on their policy. 

6. Make sure YOU have insurance, as well. 

Companies with more money are in a better position to protect their IP because, frankly, protecting IP is expensive. You have to play the cost/benefit game in determining how much you want to spend to protect it. And the best advise I can give anyone on this topic-- don't hire anyone unless you know their reputation and background. Only work with known professionals when possible. 

The second best advise is to contact a lawyer to determine what you should and should not disclose, and methods of disclosure that may be better suited to protecting your IP. 

Best of luck!

Mona

So there is no 100% way to guarantee some one won't steal what they have access to.  It's part of business.  So to sum up what's been said and give my own suggestions:

1.  Only give people access to what they absolutely need.  All major corporations practice this.  It has 0 cost besides a bit of time.

2. Have them sign an NDA.  It's not perfect but just the psychological effects of having a signed agreement can be powerful.  If you want to take it a step farther try googleing something like "Are American NDAs enforceable in India"  or what ever countries you need.  You are not the first person who wanted to outsource internationally and there is a lot of helpful info.

3. Reputation. Find a freelancer who is active on something public, for example this forum or freelancer.com. Having some place where his\her bad acts would become public and could ruin their reputation will also help keep people honest.

The simple fact is most people are good and there are thousands of interactions every day where no one screws the other over and very few of the opposite.  The bad ones are just more salient so we think they are more likely then what actually happens.

You shouldn't contract people from overseas for something like that.The laws of the country you're staying in  may not apply to the laws of another overseas. It's true you could try to take legal action, but because the people you're dealing with are overseas, it would be arduous. There's potential language barriers, timezone differences, and variations on laws. At least if you hire people in your own country it would be a lot easier for you. You could get help from a lawyer to help you write up a contract, and that would probably be enough.

I guess only trust, and of course remove  all stuff that works perfectly, like sprites/images etc