  Moir\'e quantum matter has emerged as a novel materials platform where
correlated and topological phases can be explored with unprecedented control.
Among them, magic-angle systems constructed from two or three layers of
graphene have shown robust superconducting phases with unconventional
characteristics. However, direct evidence for unconventional pairing remains to
be experimentally demonstrated. Here, we show that magic-angle twisted trilayer
graphene (MATTG) exhibits superconductivity up to in-plane magnetic fields in
excess of 10 T, which represents a large ($2\sim3$ times) violation of the
Pauli limit for conventional spin-singlet superconductors. This observation is
surprising for a system which is not expected to have strong spin-orbit
coupling. Furthermore, the Pauli limit violation is observed over the entire
superconducting phase, indicating that it is not related to a possible
pseudogap phase with large superconducting amplitude pairing. More strikingly,
we observe reentrant superconductivity at large magnetic fields, which is
present in a narrower range of carrier density and displacement field. These
findings suggest that the superconductivity in MATTG is likely driven by a
mechanism resulting in non-spin-singlet Cooper pairs, where the external
magnetic field can cause transitions between phases with potentially different
order parameters. Our results showcase the richness of moir\'e
superconductivity and may pave a new route towards designing next-generation
exotic quantum matter.
