This Valentine’s Day Secret Life of Pets Card From The Dog includes Max. The front reads 'To The Dog On Valentine's Day!’ Inside the card there is plenty of room for you to write your own message. • Dimensions: 7 X 5 inches and 184 X 133 mm envelope. The Secret life of Pets is a hugely popular animated comedy film set in New York. Following the adventures of Max the dog and his friends when their owners leave them at home alone. 2 movies have launched to date, the last one was released in 2019 and was in the top 20 worldwide box office hits in that year.