Dr. Richard Kirby from the University of Plymouth has directed a documentary about “Ocean drifters”, which he is uploading into twitter (https://twitter.com/PlanktonPundit/status/1239966980532080640). See this sniplet (from minute 2:00) of Sir David Attenborough presenting diatoms and other phytoplankton of the ocean. You can find the whole video in the youtube channel of Plymouth University:

Link to the youtube video