There are two antennas on the rooftops above Balding Avenue (up from the Grease Monkey garage). The first is guarded, so you must continue left to the red building, which has a large TV mast with a friendly spy. From there, you can grapple back to the right to reach the taller building, and enter the Greenhouse through the roof vent.
(see related question)
if you mean in spy island than you use ur bow tie to get to the antenna
He means to shoot the bowtie over to the antenna on top of the building to your right, where you will enter the greenhouse.
She is across the building with the antenna. Molly
he means to go to the building on the right, that's where the other spy is. (to be able to do that you have to get your bow tie tie and put it on the the building on the right side of you )
just use the spy grappeling bowtie to get up there
On the roof tops on the big radio tower
Use your grappling hook bowtie.
Use your grapling bow tie. It is very hard, but if you keep tring it will lead you to the green house
You have to grappel it with ur tie.
IT IS IN SPY ISLAND
The path to reach the third spy on Spy Island goes left from the Rooftops above the Grease Monkey garage. There is a guard who will attack you on the middle building, and no way to go straight up. So you go left to the reddish building and climb up. At the top, a helpful spy will suggest using the Grapple Bowtie to reach the tall antenna back to the right (atop the target building).
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