We developed a tool based on the KNIME analytics platform for the extraction and visualisation of medical time series stored in the Medical Information Mart for Intensive Care III (MIMIC III) and the related MIMIC-III Waveform Database Matched Subset. The large number of data points and the free accessibility make these data sets an attractive source for data-driven projects in the medical domain. The problem that we tackled with our tool was the lack of an easy and extensible way of selecting, reading, and visualising stored time series. Especially the fact that medical data science projects are often conducted by interdisciplinary teams called for a software solution that can be utilised by medical practitioners without programming experiences and that still offers enough flexibility for data scientists.