Angus Lordie and Domenica Macdonald are finally tying the knot. Unsurprisingly, Angus is not quite prepared and averting a wedding-day disaster falls to his best man, Matthew. When the newlyweds finally head off on their honeymoon, Angus's dog Cyril goes to stay with the Pollocks--to the delight of one member of the family, and the utter despair of another. The long-suffering Bertie knows firsthand how stringent his mother's rules can be, and he resolves to help Cyril set off on an adventure. Meanwhile, Big Lou becomes a viral Internet sensation, and the incurable narcissist Bruce meets his match in the form of a doppelganger neighbor, who proposes a plan that could change both their lives.