RORY: Lane. How did you know I was here?
LANE: Telescope. I got a clean shot at Luke’s. I saw you and your mom go in.
Lane is now having “the mother of all groundings” since Mrs Kim found out that she had secretly been talking to Henry, and had attempted to have a date with him. She is confined to the house, not even being permitted to attend school (Mrs Kim has told Stars Hollow High that Lane has a highly contagious illness, and gained permission to home school her daughter for two weeks).
Lane using a telescope to spy on Rory so she can feel connected to the outside world may be an allusion to the 1954 mystery thriller film Rear Window. Directed by Alfred Hitchcock, it stars James Stewart as a photographer recuperating from a broken leg. Confined to a wheelchair in his Greenwich Village apartment, he uses binoculars, and the telescopic lens of his camera, to spy on his neighbours, solving a murder mystery in the process.
Rear Window was the #8 film of 1954 at the box office. It received critical acclaim, and is considered one of the greatest films of all time.