This episode was half and half for me. It was good in ways that it helped create a foundation for Chris and Sivea's up-and-coming friendship, more Grant backstory and more Grant/Callen developement. But beyond that, didn't particualy enjoy it.
The problem of such a large cast once again showed in this episode. In that by having such a large amount of characters, it seemed to bog down stuff at places. We'd got 3 scientists dying, doing pretty much nothing - no tension there BTW. It's about time someone was topped off.
This sort of episode would have worked alot better with only a few characters in the main focus. You could have devoted more time to Sivea/Chris and helped define them more.