Before the making of 2001: A Space Odyssey, IBM consulted with Stanley Kubrick. But as development progressed, he began to worry that the company would feel "swindled" by a film about a murderous machine whose name could be found by shifting each letter in "IBM" by one. Letters of Note has published correspondence between Kubrick and Roger Caras of Polaris Productions, with Caras offering assurance that though IBM was aware that "HAL actually causes human deaths," the company would be fine as long as it was not singled out as an advisor on the computer — especially since HAL was "obviously not an IBM machine."