So Sally Field plays a widow who works as a cleaner at the town aquarium, where mostly schoolchildren stream in, smearing their hands on the glass and dirtying the floor with gum. Take note: There is no gum that cannot be removed, if one only tries hard enough. There is a right way and a wrong way to do things, Field keeps repeating, and one must choose the right one. The talkative octopus, voiced softly by Alfred Molina, also has a well-reasoned philosophy of life, though not one that has exactly prevented him from ending up in the glass tank from which he repeatedly escapes, only to be poured back into it. At times, it recalls “My Octopus Teacher,” the Oscar-winning documentary in which the eight-armed mollusk of the title serves as a life teacher for a naturalist going through a midlife crisis.