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We infer the gas kinematics, diagnostics and ionic radial profiles, distanceand central star parameters, nebular photo- ionization model, spatial structureand evolutionary phase of the PN NGC 6741 by means of long-slit high-resolutionspectra at nine position angles. NGC 6741 (distance ~2.0 kpc, age ~1400 yr,ionized mass Mion ~0.06 Mo) is a dense (electron density up to 12,000 cm^(-3)),high-excitation, almost- prolate ellipsoid, surrounded by a sharplow-excitation skin (the ionization front), and embedded into a spherical(radius ~ 0.080 pc), almost-neutral, high-density (n(HI) ~7 x 10^3 atomscm^(-3)) halo containing a large fraction of the nebular mass (Mhalo>0.20 Mo).The kinematics, physical conditions and ionic structure indicate that NGC 6741is in a deep recombination phase, started about 200 years ago, and caused bythe quick luminosity drop of the massive (M*=0.66-0.68 Mo), hot (logT* ~ 5.23)and faint (log L*/Lo ~ 2.75) post--AGB star, which has exhausted thehydrogen-shell nuclear burning and is moving along the white dwarf coolingsequence. The general expansion law of the ionized gas in NGC 6741, Vexp (kms^(-1)=13 x R", fails in the innermost, highest-excitation layers, which moveslower than expected. The observed deceleration is ascribable to the luminositydrop of the central star, and appears in striking contrast to recent reportsinferring that acceleration is a common property of the Planetary Nebulaeinnermost layers. Some general implications on the shaping mechanisms ofPlanetary Nebulae are discussed.

The 3-D shaping of NGC 6741: A massive, fast-evolving Planetary Nebula at the recombination-reionization edge