Persian arts of the book reached new heights under the patronage of the Timurids, in particular in the atelier of prince Bāysunghur (1399–1433) in Herat. This paper introduces a dual-text manuscript produced there in 833/1430, now held in the Suleymaniye Library in Istanbul, which has previously escaped scholarly attention. Up until now its scribe, Saʿd Mashhadī, has been known only for his copy of the Tārīkh-i Jahāngushāy of ʿAtā-Malik Juvaynī (834/1431). He has been identified with Maulānā Saʿd al-Dīn named in the ʿArża-dāsht, the report written by Bāysunghur's chief librarian, Jaʿfar Tabrīzī. On the basis of the report and a study of the calligraphy, I argue Saʿd Mashhadī penned a third manuscript for Bāysunghur, an early copy of the Zubdat al-tawārīkh, c.829/1426. This article attempts to provide a fuller picture of the calligrapher. A number of biographical dictionaries mention a contemporary called Ḥāfiẓ Saʿd, a follower of Qāsim Anvār, who was a prominent poet and riddle writer. Beginning with a poetic connection between the two names in a biographical work, and pursuing an in-depth study of his Dīvān, which, through riddles, reveals an association with Bāysunghur's atelier, I suggest that Saʿd Mashhadī and Ḥāfiẓ Saʿd could be the same person. Whether or not this is the case, this study sheds new light on an important but little known court poet and Sufi and a calligrapher in the royal atelier.