public interface IDataLayer
{
    dynamic GetItem(int id);
    dynamic SaveItem(dynamic item);
}

public class MockDataLayer : IDataLayer
{
    public dynamic GetItem(int id)
    {
        dynamic item = new System.Dynamic.ExpandoObject();
        item.Id = id;
        item.Name = "Some name";
        return item;
    }
    public dynamic SaveItem(dynamic item)
    {
        return item;
    }
}
public class MainController : Controller
{
    public ActionResult Display(int id = 0)
    {
        dynamic viewModel = Global.DataContext.GetItem(id);
        return View(viewModel);
    }
}
public class Global : System.Web.HttpApplication
{
    public static IDataLayer dataContext;

    protected void Application_Start(object sender, EventArgs e)
    {
        IKernel kernel = new StandardKernel();

        kernel.Bind<IDataLayer>().To<MockDataLayer>();
        dataContext = kernel.Get<IDataLayer>();

        RouteTable.Routes.MapRoute("", "{id}", new { controller = "Main", action = "Display", id = UrlParameter.Optional });
    }
}

private static void RegisterServices(IKernel kernel)
{
    kernel.Bind<IDataLayer>().To<MockDataLayer>().InRequestScope();
}

var dataContext = DependencyResolver.Current.GetService<IDataLayer>();