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We present 65 optical spectra of the Type Ia supernova SN 2012fr, of which 33were obtained before maximum light. At early times SN 2012fr shows clearevidence of a high-velocity feature (HVF) in the Si II 6355 line which can becleanly decoupled from the lower velocity "photospheric" component. This Si II6355 HVF fades by phase -5; subsequently, the photospheric component exhibits avery narrow velocity width and remains at a nearly constant velocity ofv~12,000 km/s until at least 5 weeks after maximum brightness. The Ca IIinfrared (IR) triplet exhibits similar evidence for both a photosphericcomponent at v~12,000 km/s with narrow line width and long velocity plateau, aswell as a high-velocity component beginning at v~31,000 km/s two weeks beforemaximum. SN 2012fr resides on the border between the "shallow silicon" and"core-normal" subclasses in the Branch et al. (2009) classification scheme, andon the border between normal and "high-velocity" SNe Ia in the Wang et al.(2009a) system. Though it is a clear member of the "low velocity gradient"(LVG; Benetii et al., 2005) group of SNe Ia and exhibits a very slowlight-curve decline, it shows key dissimilarities with the overluminous SN1991T or SN 1999aa subclasses of SNe Ia. SN 2012fr represents a well-observedSN Ia at the luminous end of the normal SN Ia distribution, and a keytransitional event between nominal spectroscopic subclasses of SNe Ia.

Spectroscopic Observations of SN 2012fr: A Luminous Normal Type Ia Supernova with Early High Velocity Features and Late Velocity Plateau