Laminated film, method for producing same, and polarizing plate

A layered film comprising:

• a first layer formed of a first resin;
• a second layer formed of a second resin;
• and a third layer formed of a third resin, provided in this order, wherein
• the second resin contains an alkoxysilyl group-modified product of a hydrogenated product of a block copolymer,
• a moisture content of the second resin as measured by the Karl-Fischer method after the second resin is immersed in water at 37° C. for 24 hours and then allowed to stand in an environment at 23° C. and a humidity of 70% for 24 hours is 0.020% by weight or less,
• the second resin has a flexural modulus lower than a flexural modulus of the first resin and lower than a flexural modulus of the third resin,
• one or both of the first resin and the third resin contain a polymer containing an alicyclic structure,
• a water vapor transmission rate of the first resin as measured in accordance with JIS K7129 B(1992) when the resin is in a form of a 100 μm-thick film is 5 g/(m2·day) or less, and
• a ratio of a sum of a thickness of the first layer and a thickness of the third layer relative to a thickness of the second layer is 1 or more and 4 or less.