var client = new ServiceClient("<ApiKey>");
var movies = await client.Movies.GetTopRatedAsync(null, 1, cancellationToken);

foreach (Movie m in movies.Results)
{
	var movie = await client.Movies.GetAsync(m.Id, null, true, cancellationToken);

	foreach (MediaCast c in movie.Credits.Cast)
	{
		var person = await client.People.GetAsync(c.Id, true, cancellationToken);

		foreach (Image img in person.Images.Results)
		{
			string filepath = Path.Combine("People", img.FilePath.TrimStart('/'));
			await DownloadImage(img.FilePath, filepath, cancellationToken);
		}
	}
	foreach (MediaCrew c in movie.Credits.Crew)
	{
		var person = await client.People.GetAsync(c.Id, true, cancellationToken);

		foreach (Image img in person.Images.Results)
		{
			string filepath = Path.Combine("People", img.FilePath.TrimStart('/'));
			await DownloadImage(img.FilePath, filepath, cancellationToken);
		}
	}
}

static async Task DownloadImage(string filename, string localpath, CancellationToken cancellationToken)
{
    if (!File.Exists(localpath))
    {
        string folder = Path.GetDirectoryName(localpath);
        Directory.CreateDirectory(folder);

        var storage = new StorageClient();
        using (var fileStream = new FileStream(localpath, FileMode.Create, 
			FileAccess.Write, FileShare.None, short.MaxValue, true))
        {
            try { await storage.DownloadAsync(filename, fileStream, cancellationToken); }
            catch (Exception ex) { System.Diagnostics.Trace.TraceError(ex.ToString()); }
        }
    }
}