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Daws Butler as Loopy De Loop (voice) |
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Hal Smith as Elderly Woman / Mr. Hyde (voice) |
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Don Messick as Car Owner / Dr. Jekyll (voice) |
| Directing | Joseph Barbera | Director |
| Directing | William Hanna | Director |
| Writing | Warren Foster | Story |
| Production | Joseph Barbera | Producer |
| Production | William Hanna | Producer |
