The absorption properties of ultrathin conductive films are of fundamental significance in electromagnetics and photonics, impacting applications from radar stealth to two-dimensional material optoelectronics. For decades, a 50% absorption limit has been considered intrinsic to such films in symmetric environments, regardless of frequency or incident angle. Here, we demonstrate the breaking of this long-standing limit under grazing incidence, where the absorption was regarded as negligible due to extreme impedance mismatch. We reveal a previously unknown absorption limit of $2\sqrt{2}-2\approx 82.8\%$ for grazing transverse-magnetic waves on arbitrarily thin, highly conductive films. This exceptional absorption arises from a pseudo-Brewster effect with minimal reflection $3-2\sqrt{2}\approx 17.2\%$ and vanishing skin depth of grazing waves. Remarkably, the enhanced absorption is sustained across an ultrabroad frequency range. Terahertz experiments using deep-subwavelength doped silicon wafers validate our theoretical predictions. These findings fundamentally advance our understanding of wave-matter interactions at deep-subwavelength scales and pave the way for extreme-angle photonic and electromagnetic devices.

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• Classical optics
• Light propagation, transmission & absorption
• Metasurfaces