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From Oct. 2019 to Apr. 2020, LAMOST performs a time-domain spectroscopicsurvey of four $K$2 plates with both low- and med-resolution observations. Thelow-resolution spectroscopic survey gains 282 exposures ($\approx$46.6 hours)over 25 nights, yielding a total of about 767,000 spectra, and themed-resolution survey takes 177 exposures ($\approx$49.1 hours) over 27 nights,collecting about 478,000 spectra. More than 70%/50% oflow-resolution/med-resolution spectra have signal-to-noise ratio higher than10. We determine stellar parameters (e.g., $T_{\rm eff}$, log$g$, [Fe/H]) andradial velocity (RV) with different methods, including LASP, DD-Payne, andSLAM. In general, these parameter estimations from different methods show goodagreement, and the stellar parameter values are consistent with those ofAPOGEE. We use the $Gaia$ DR2 RV data to calculate a median RV zero point(RVZP) for each spectrograph exposure by exposure, and the RVZP-corrected RVsagree well with the APOGEE data. The stellar evolutionary and spectroscopicmasses are estimated based on the stellar parameters, multi-band magnitudes,distances and extinction values. Finally, we construct a binary catalogincluding about 2700 candidates by analyzing their light curves, fitting the RVdata, calculating the binarity parameters from med-resolution spectra, andcross-matching the spatially resolved binary catalog from $Gaia$ EDR3. TheLAMOST TD survey is expected to get breakthrough in various scientific topics,such as binary system, stellar activity, and stellar pulsation, etc.

LAMOST Time-Domain Survey: First Results of four $K$2 plates