This took me an unforgiveably long time to figure out. It's the 1963 movie
The Old Dark House by schlockster William Castle, starring the late Tom Poston and the even later Robert Morley.
An imdb.com reviewer notes: "Joyce Grenfell as the intrepid knitter stands out in my memory... Her character knitted by the mile...She was murdered by having her knitting needles stuck cross ways through her neck."