Seems mighty chummy with the dog all of a sudden.

Unexplained calls to F. Lee Bailey's 900 number on your bill.

He actually does have your tongue.

You find a stash of "Feline of Fortune" magazines behind the couch.

Cyanide pawprints all over the house.

You wake up to find a bird's head in your bed.

As the wind blows over the grassy knoll in downtown Dallas, you get a faint whiff of catnip.

Droppings in litter box spell out "REDRUM."

Catch him with a new mohawk looking in the mirror saying, "Mew looking at me? Mew looking at me?"

Takes attentive notes every time "Itchy and Scratchy" are on.

You find blueprints for a Rube Goldgerg device that starts with a mouse chased into a hole and ends with flaming oil dumped on your bed.

Has taken a sudden interest in the wood chipper.

Instead of dead birds, leaves cartons of Marlboros on your doorstep.

Ball of yarn playfully tied into a hangman's noose.

You find a piece of paper labeled "MY WIL" which says "LEEV AWL 2 KAT."

Now sharpens claws on your car's brake lines.