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A very close high‐speed video observation of lightning attachment to a building revealed novel details regarding the leader streamer zone dynamics. Upward leaders propagate in a steady and unbranched manner, displaying a uniformly luminous corona brush. The exception being the upward connecting leader (UCL) just before connection, when its streamer zone increases in size and develops a more filamentary pattern. Downward negative leaders have 3‐m long multiple streamers emanating from each negative leader tip. On some occasions, plasma formations known as space stems are seen to form in the location previously occupied by negative streamers. Space stems have luminosities comparable to the main leader channel, but are detached from it by 4 m. Some space stems display streamers of their own, including cases where streamers are emanating from both ends. The space stem formation hampered the propagation of the negative leader that was closest to the UCL. Plain Language Summary: A serendipitous close observation of a natural lightning flash revealed novel details of the lightning attachment process to residential buildings in highly populated areas. A staggering total of 31 lightning precursor channels (called leaders) were launched from nearby buildings in an attempt to intercept the down coming negative leaders. The upward positive leaders propagate almost in a straight path manner, do not branch, and display a uniformly luminous "corona brush" at their tips. This contrasts with the negative leaders coming down from the cloud, which present substantial branching and have numerous filaments (called streamers) emanating from their tips. The high‐speed and high‐resolution images obtained also revealed that, in some cases, the negative leaders display a luminous formation that is about 2 m long and is detached from the main channel by about 4 m. These observations consist of one of the rare sightings of these luminous formations known in the peer‐reviewed literature as "space stems." It is understood that space stems play a key role in the stepped propagation of negative leaders. In these observations, it seems that they hamper the leader propagation, making the upward connecting leader intercept a different downward branch, which was originally more distant from the striking point. Key Points: Very close high‐speed video observation of lightning attachment reveals details of corona brush, streamers and space stemsStreamer zone of upward connecting leader increases in size and develops a more filamentary patternSome space stems display streamers emanating from both ends, forming an embryonic bidirectional space leader [ABSTRACT FROM AUTHOR]